The momentum over horsepower debate | Column

David S.
By David S. Wallens
Jan 14, 2022 | BRZ, GT86 | Posted in Columns | From the Nov. 2018 issue | Never miss an article

It is the evil weevil, the rock-solid, steely-eyed grim reaper of sporting cars, the paragon of knife-edged incisiveness and buttoned-down insanity.”

Is this lofty praise for one of the new 700-horsepower Challengers? A twin-turbo Porsche? An Exocet powered by a half-dozen superbike engines and a deranged ferret?

D, none of the above. It’s Car and Driver’s lede for its original road test on the 1984 Porsche 911 Carrera. Total engine output? Thanks to the introduction of Bosch’s Motronic injection, along with a bump in displacement from 3.0 liters to 3.2, horsepower had finally reached an even 200. That’s way less than most any new minivan. Top speed? A blinding-for-the-day buck-50 or so. 

I’m lucky to own one of these Porsches, and yes, it’s still the finest car I have ever driven. You can quote me on that. Do faster models from the brand exist? Absolutely. But, like Baby Bear’s bed, this one’s just right. It has the perfect amount of power for the chassis, near-telepathic steering, and one of the most iconic views over the bow. Then there’s the olfactory treat of oil mixed with leather mixed with history. 

One of my other favorite cars produces the same horsepower figure, yet people “in the know” said that I’d hate it: Not enough power. Needs a turbo. Too slow. Boring. 

The object of their scorn? The Subaru BRZ. After living with one for more than a year, I can state that they were totally wrong. I unequivocally love it. It’s fun and rewarding to drive on track, and perfect for around-town use. It gobbles up the highway miles with ease. It’s good on gas, too, and offers plenty of outward visibility. Even the trunk is big enough for my needs. 

Then add in comfy seats, a precise shifter, perfect pedal placement and, if I can admit, fine lines. Half a dozen years afters its introduction, a BRZ or one of the clones from Toyota still turns my head. 

The haters have hated on the BRZ since day one for the simple fact that it only makes 200 horsepower. Subaru could turbocharge it, but then cost, complexity and weight would all go up. The BRZ would no longer be a BRZ. And why would Subaru make a car that competes with its iconic WRX for showroom traffic? 

Some of my other faves also come from the 200 club: the Integra Type R, MR2 Turbo, a Miata with some boost, the all-conquering E30-chassis M3, my wife’s Civic Si. And I think we can now welcome the ND-chassis MX-5 to that group, as it’s close enough.

Really, though, this is more than numbers. This is about cars that are quick enough to be fun, yet challenging to drive. They force you to hit your marks. You can’t mask mistakes with horsepower. Brake too early, and the pack will leave you in the dust. 

Reeling in theoretically faster cars becomes your goal. Stomp the middle pedal at the one and a half, nail the apex, track all the way out–use the curbs if you have to. Do it correctly, and the horsepower deficit quickly evaporates. 

On the street, you can enjoy these cars without being a menace to society. A little while back I was cutting through Jacksonville in the BRZ. The interstate makes a right-left, downhill jog just before downtown. Of course I was heel-toeing the entire way. A glance ahead showed that I was keeping pace with a few minivans. Whatever, I was having fun. My M3 doesn’t get interesting until it’s traveling way too fast for street conditions. 

What’s better than a car making 200 horsepower? How about one making about half that. Don’t believe me? I present Exhibits A though G: the original Miata, a slightly tweaked Rabbit GTI, the CRX Si, the first MR2, a well-tuned Triumph TR6 and a first-generation RX-7.

Also a fan of momentum over horsepower? Let’s hear it.

Join Free Join our community to easily find more BRZ and GT86 articles.
Comments
View comments on the GRM forums
adam525i (Forum Supporter)
adam525i (Forum Supporter) GRM+ Memberand HalfDork
10/14/20 9:30 a.m.

I love my momentum car, it's right around that 200 hp mark with a bit more torque. When I go to a track it's for the corners and not the straights, carrying every bit of speed through them is my goal, when you get it right and use ALL of the track nothing feels better. I've had ride alongs in 500 hp Mustangs and 600 hp Camaro's and they were fun getting pushed back into the seat all the way down the straights but the laps in an 8th gen Civic Si on Hoosier R7's will always stick with me and make me lust for more grip and corner speed.

flatlander937
flatlander937 HalfDork
10/14/20 9:48 a.m.

Every car is a momentum car if you're driving it correctly.

Streetwiseguy
Streetwiseguy MegaDork
10/14/20 10:06 a.m.
flatlander937 said:

Every car is a momentum car if you're driving it correctly.

Want to thumbs up this more than once.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/14/20 10:08 a.m.

Momentum is grip vs power. Its a ratio thing, not absolute. Put crap tires on a 1.6 Miata and it transforms from a momentum car to a point and shoot. 
 

There are F1 cars that are momentum cars by the reference of the rest of the field. 

Ben Jolly
Ben Jolly New Reader
10/14/20 11:02 a.m.

I am happy the very powerful vehicles exist. A couple weeks ago I watched Ford vs. Ferrari and then I was on Shelby's website looking at 500 hp+ cars. I've ridden in couple, they are astounding.

Even more astounding are the LS powered Miatas I have ridden including the one in the avatar of the poster above me. 

I'm still in the momentum car fan club though. I am thankful that I can do motorsports in my 30s, but I couldn't do it with a tire/brake/insurance eating monster, so a NC Miata is my choice instead. 

I think R&T's Kyle Kinard summed it up pretty well in this article from nearly 3 years ago:

Can You Teach Speed Without a Fast Car?

rezisehtnys
rezisehtnys New Reader
10/14/20 11:51 a.m.

I'm much happier with my 142hp Miata than I ever was with my 305hp Firebird, though I'd be lying if I said I didn't miss the V8 at times.  More so the soundtrack and copious amounts of torque everywhere than anything else, I rarely ever fully utilized the horsepower aspect.  I think a 200-300hp V8 in a Miata would be the perfect car for me, maybe someday soon.

adam525i (Forum Supporter)
adam525i (Forum Supporter) GRM+ Memberand HalfDork
10/14/20 12:57 p.m.
flatlander937 said:

Every car is a momentum car if you're driving it correctly.

I've thought about this a bit as I compare lines in my low power car to my cousin's LT1 1LE Camaro with the first corner at Toronto Motorsports Park in mind. There are two main straights at that track separated by corner 1. For me my goal is to carry as much as my speed as possible through that corner as that will give me the best speed down the following straight. That means I'm not unwinding the wheel as I track out to the exit curb but I am flat on the throttle (low power car) on the edge of grip. With his extra 400 hp in my mind it would make sense to sacrifice a bit of corner speed there which would allow him to get the car straighter sooner allowing him to use his power advantage longer down that second straight and possibly result in a lower lap time.

To me that would not be a momentum car if you were driving it that way and may be quicker overall. Am I right or wrong? The answer would lie in the data at the end of the day.

nderwater
nderwater UltimaDork
10/14/20 12:58 p.m.

It's been my experience that 'fun to drive' is not directly linked to price or horsepower.  I agree with a lot of points in the column, and there are plenty of expensive, high powered cars that I'm not interested in.

That said, I disagree with David when he says that "Subaru could turbocharge it, but then... The BRZ would no longer be a BRZ."  Adding power enhances that car's personality like turning up a volume knob, and it's a more enjoyable ride because of it. 

Tom1200
Tom1200 Dork
10/14/20 1:15 p.m.

I've been on track with everything from 70 to 700hp. The higher horsepower cars are more of an adrenaline rush but they are not "more" fun.

The reason it's so easy to get it wrong in the higher horsepower really isn't because of the horsepower, it's more to do with the weight and arriving at places faster. It's much easier to miss your marks.

I obviously prefer momentum cars as I'm a drive a slow car fast guy. Also the tire bill has a lot to do with it.

My perfect track car is a 150-200hp single seater as that splits the two extremes nicely.

ProDarwin
ProDarwin MegaDork
10/14/20 1:24 p.m.
flatlander937 said:

Every car is a momentum car

This is my thought.  Is there a car where you wouldn't want to maximize momentum?

nderwater
nderwater UltimaDork
10/14/20 1:24 p.m.
Tom1200 said:

I've been on track with everything from 70 to 700hp. The higher horsepower cars are more of an adrenaline rush but they are not "more" fun.

The reason it's so easy to get it wrong in the higher horsepower really isn't because of the horsepower, it's more to do with the weight and arriving at places faster. It's much easier to miss your marks.

Agreed, I've tracked a couple of 911 Turbos and they were a little terrifying because my mind had a hard time keeping up.  But I'm sure that the exact same rush could be had in a shifter kart that costs less than the OE wheel and tire package for those Porsches.

nderwater
nderwater UltimaDork
10/14/20 1:52 p.m.

In reply to watkins089 :

Surreal canoe speak is surreal.

dps214
dps214 HalfDork
10/14/20 1:58 p.m.
Keith Tanner said:

Momentum is grip vs power. Its a ratio thing, not absolute. Put crap tires on a 1.6 Miata and it transforms from a momentum car to a point and shoot. 
 

There are F1 cars that are momentum cars by the reference of the rest of the field. 

My favorite part of autocrossing my friend's GT3 is that, compared to its class competition, it's a momentum car. A 435hp momentum car. Best of both worlds!

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/14/20 2:01 p.m.
adam525i (Forum Supporter) said:
flatlander937 said:

Every car is a momentum car if you're driving it correctly.

I've thought about this a bit as I compare lines in my low power car to my cousin's LT1 1LE Camaro with the first corner at Toronto Motorsports Park in mind. There are two main straights at that track separated by corner 1. For me my goal is to carry as much as my speed as possible through that corner as that will give me the best speed down the following straight. That means I'm not unwinding the wheel as I track out to the exit curb but I am flat on the throttle (low power car) on the edge of grip. With his extra 400 hp in my mind it would make sense to sacrifice a bit of corner speed there which would allow him to get the car straighter sooner allowing him to use his power advantage longer down that second straight and possibly result in a lower lap time.

To me that would not be a momentum car if you were driving it that way and may be quicker overall. Am I right or wrong? The answer would lie in the data at the end of the day.

That's my point. The reason you're taking different lines is not because one car has more horsepower than another - it means one car has more grip than horsepower. Up the grip on a high power car and you're back to those lines that emphasize corner exit speed instead of corner exit traction. You can have a 400+ hp momentum car, but you're going to have to build the chassis for it.

My 500 hp Miata has been a momentum car or a point and shoot car depending on what I'm running against. 

adam525i (Forum Supporter)
adam525i (Forum Supporter) GRM+ Memberand HalfDork
10/14/20 2:24 p.m.

In reply to Keith Tanner :

Fair enough and that is a really good point. So it's not that every car is a momentum car but every car can be a momentum car. I like that.

350z247
350z247 New Reader
10/14/20 2:25 p.m.

If a RWD car has less than 300hp and can't hit 60 in less than 6 seconds, I'm gonna get bored real quick. Of course, there are a lot of variables: suspension set up, weight, wheelbase, intended use, ect, but that really seems to be my lower limit. Miatas are great fun in a parking lot, but on anything larger, I just need more power to have  as much fun as possible. Barely cracking 100mph on a straight is incredibly frustrating. I'm assuming I would feel the same way in a BRZ except worse based on how the stock dyno graph looks.

That being said, I also don't want to be driving a S197 GT500 on track either...

Tom1200
Tom1200 Dork
10/14/20 3:37 p.m.

I get the perspective on horsepower; I envision John Force driving a Veyron, getting out of the car and saying "needs more power" . 

Coming from motorcycles to it's very difficult for me to find something that "feels" fast up the striaghts.

I'm willing to live with the compromise of something like a Miata or BRZ in exchange for lower running costs.

The other factor (for me) is getting the most out of it. A couple of years ago I drove someone's 911 GT-3RS, while I was 4 seconds a lap faster than the owner I'm also keenly aware that one of the factory guys would be 4 seconds (or more) faster than me. I'm not in a place where I'm OK with only getting 80-90% out of a car. 

Eventually I'll likely be OK with driving 80-90% as I do that with with my 500cc dirt bike but I'm still a 125 rider at heart.

 

buzzboy
buzzboy Dork
10/14/20 3:54 p.m.

I'm not a great driver. I know that. I get 5-10hrs of track time yearly and it's all green flag w2w. Without getting to practice beyond the traction limit I don't want to learn it during a race. I'm happy to have a car that is not traction limited. We're at 174bhp 243ft*lbs in a ~3000lbs car with plenty of tire.

mazdeuce - Seth
mazdeuce - Seth Mod Squad
10/14/20 3:54 p.m.
Keith Tanner said:

Put crap tires on a 1.6 Miata and it transforms from a momentum car to a point and shoot. 
 

And these are my favorite cars on earth. 

 

Driven5
Driven5 UltraDork
10/14/20 4:16 p.m.

Forget the "every car is a momentum car" nonsense...Keith hit the nail on the head!  While momentum is important to all cars, how that momentum is best applied is what differentiates a 'momentum car'.

Over the years, I've found that I vastly prefer the perception of performance over absolute performance.

Tom1200
Tom1200 Dork
10/14/20 4:42 p.m.

Ding ding ding Driven5 summed it up perfectly.

 

ProDarwin
ProDarwin MegaDork
10/14/20 7:29 p.m.
Keith Tanner said:

That's my point. The reason you're taking different lines is not because one car has more horsepower than another - it means one car has more grip than horsepower. Up the grip on a high power car and you're back to those lines that emphasize corner exit speed instead of corner exit traction. You can have a 400+ hp momentum car, but you're going to have to build the chassis for it.

My 500 hp Miata has been a momentum car or a point and shoot car depending on what I'm running against. 

I'm having trouble following this.

Your 500hp miata - for your fastest lap time there is only one optimized line, right?  (assuming no traffic here)  If you subtracted 250 hp, you would drive a different line to maximize your laptime?

I've always thought of the perfect line as staying relatively constant, just the speed at which you can trace it goes up as you add grip and horsepower.  All cars want to maximize the speed carried through the corner, right?

Tom1200
Tom1200 Dork
10/14/20 7:56 p.m.

ProDarwin when driving my 80whp Datsun 1200 in certain corners I take the shortest distance because it saves time. I will double apex certain decreasing radius corners vs the traditional late apex. I also may drive the bottom lane of big sweepers. 

By contrast my Formula 500 doesn't require any of these antics.

As you move along between 80 and 800hp you'll find yourself adjusting your lines incrementally.

MotorsportsGordon
MotorsportsGordon HalfDork
10/14/20 8:55 p.m.

The Chaparral 2J proved you can have horsepower and be a momentum car. To quote Jim hall at laguna seca everyone thought vic elford had lost his breaks,truth was he hardly had to use them at all.

 

mazdeuce - Seth
mazdeuce - Seth Mod Squad
10/14/20 9:13 p.m.

In reply to ProDarwin :

There isn't an ideal line. Even something simple like changing tires, or adjusting aero on a car will change the fastest line.

ProDarwin
ProDarwin MegaDork
10/14/20 9:17 p.m.

Aero makes perfect sense.

Does anyone have a top view that can illustrate how the line would change when you add/remove mechanical grip or horsepower?

adam525i (Forum Supporter)
adam525i (Forum Supporter) GRM+ Memberand HalfDork
10/14/20 9:51 p.m.

In reply to ProDarwin :

You made me do some googling but it seems to have been worth it, take a read through these two blog posts and see what you think.

https://yousuckatracing.wordpress.com/2016/10/16/math-on-the-racing-line-part-1/

https://yousuckatracing.wordpress.com/2016/10/22/math-on-the-racing-line-part-2/

They really highlight how much of a crutch power can be using his hypothetical corner and grip/acceleration levels. The Miata could lose 1.39 seconds in this corner with different lines whereas the Corvette using those same lines could only lose 0.22 seconds from best line to worst. 

Tom1200
Tom1200 Dork
10/14/20 10:41 p.m.

ProDarwin I will attempt this without drawings, note that some of this may be peculiar to vintage race cars, specifically to my Datsun on bias ply Hoosiers. I'll use a medium speed 90 degree corner as an example.

80whp Datsun; just shy of the known turn in point I will actually ever so slightly over rotate the car via trail braking, this has a triple effect of shedding that last little bit of speed allowing me to take a slightly tighter line and pick up the throttle earlier.  What you would see if I drew a line would be a 10 degree deviation from straight ahead for the first 1/8th of the corner followed by a 60 degree arc from 1/8th through 3/8ths, by 1/2 I'm fully on the throttle and unwinding the wheel to free up the car the last 20 degrees of corner. In general I end up with a progressive and slight 4 wheel drift on exit.

So while I'm slightly pinching the corner on the entrance I'm also carrying a bit more entrance speed that needs to be scrubbed off (we're taking 1/2- 3/4 mile an hour to be scrubbed off).

By contrast in the Formula 500 I would use a steady arc with the apex at the geometric center.  This is becuase the car is on slicks and it does what you ask it. It also has the ability to spin the tires mid corner so even if you were back to the throttle earlier you couldn't put more power down anyway. The F500 is also much more straightforward to drive. Power wise it keeps up with 450hp to 480hp road cars.

Most of my experience with down force is with my old D-Sports Racer. My previous description of the line used in the Datsun may come into play here. Because the car stuck you could use more aggressive steering inputs; if there was a straight after said 90 degree corner I'd pinch the entrance in order to be opening up the wheel to flatten out the car and get the power down earlier. If the 90 degree corner only had a short chute to the next corner then I'd use a line like the F500. The D-sports would out accelerate Dodge Vipers but because of the down force the line options were pretty limitless. 

 

 

frenchyd
frenchyd PowerDork
10/14/20 10:56 p.m.

The most fun I've had racing is with a near stone stock MGTD. 54 horsepower around 2000 pounds. 
     Honest drafting being pulled along by a MGTC with a supercharger that increased his horsepower  to 70.  But by staying in his draft with the windshield folded down I could go just as fast as he could then my "modern" front suspension allowed me to out corner him only to be repassed on the next straight.  By sand bagging just a little I set him up for a last corner pass and held on to lead at the Checker by 2 inches. 
After the race we laughed and patted each other's back. I didn't stop grinning for the whole day. Everyone else in our group felt the same. 
Please don't tell me you need 700+ horsepower to race.  Maybe your ego does but that's not where the fun is.  

ProDarwin
ProDarwin MegaDork
10/15/20 7:58 a.m.
adam525i (Forum Supporter) said:

They really highlight how much of a crutch power can be using his hypothetical corner and grip/acceleration levels. The Miata could lose 1.39 seconds in this corner with different lines whereas the Corvette using those same lines could only lose 0.22 seconds from best line to worst. 

Thanks for those links.  Interesting reading.

Here is how I interpret some of that:  

1) I'm not sure how far out the poster carried that simulation.  IMO, it requires a full circuit for it to be comparable, otherwise time is only 1/2 of the equation.  The Corvette is 0.01 faster on the rally line, however what is the exit speed?  I suspect its slightly faster on the late apex line, meaning unless there is a LH turn immediately approaching, the late apex is truly the faster line.

2) Above said, the late apex line is truly the fastest line for both the momentum car and the horsepower car.  Sure, the horsepower car suffers less when its off line, but its ideal ine is the same line.

 

For the snow situation, see point #1 above.  Its hard to tell which is faster without an appreciable straight or upcoming turn after the corner.

 

volvoclearinghouse
volvoclearinghouse PowerDork
10/15/20 8:42 a.m.

We've LeMons raced a Volvo 122 with perhaps 110-120 HP in a warm B20, and had a riot.  Our current car has a 350-ish HP big block in a heavier chassis and it's also fun.

Drag racing on the street anymore is pretty much dead.  I realized this last weekend when some CUV (I still don't know what it was, nor do I care) beat me from a stoplight in my ~220 HP Jaguar 3.8s.  Any modern car has too many turbochargers, transmission gears, and variably-timed valves for all but the hottest older iron.  Our LeMons car _might_ have beaten it, but it's a caged, single seat car with no interior, heat, wipers, or glass. 

Real driver skill shows up in the corners.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/15/20 8:44 a.m.
ProDarwin said:
Keith Tanner said:

That's my point. The reason you're taking different lines is not because one car has more horsepower than another - it means one car has more grip than horsepower. Up the grip on a high power car and you're back to those lines that emphasize corner exit speed instead of corner exit traction. You can have a 400+ hp momentum car, but you're going to have to build the chassis for it.

My 500 hp Miata has been a momentum car or a point and shoot car depending on what I'm running against. 

I'm having trouble following this.

Your 500hp miata - for your fastest lap time there is only one optimized line, right?  (assuming no traffic here)  If you subtracted 250 hp, you would drive a different line to maximize your laptime?

I've always thought of the perfect line as staying relatively constant, just the speed at which you can trace it goes up as you add grip and horsepower.  All cars want to maximize the speed carried through the corner, right?

When I'm chasing a 911 with an LS7 shoved up the rear, I'm struggling to get traction off slow corners by comparison so I'm trying to preserve momentum. So I'm driving the momentum car in this case.

When I'm chasing something with more grip but less horsepower (say, a well set up E36), I'm the one with all the acceleration so in that case I'm driving the point and shoot car. My lines don't change, but my role does.

If you have the ability to put down serious acceleration coming out of a corner, you'll run a different line because it allows you to start to accelerate sooner. Giving up 5 mph mid-corner is worth it if you can add 10 mph to your exit speed, because you get that extra speed allll the way to the next braking zone.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/15/20 8:50 a.m.
frenchyd said:

Please don't tell me you need 700+ horsepower to race.  Maybe your ego does but that's not where the fun is.  

You do if the guys you're racing have 1000+. That's the same equation you had so much fun with, just scaled up. It adds new corners to the track - you don't understand why the Andretti hairpin at Laguna Seca is called "turn 2" until you have some horsepower and you discover the very exhilarating turn 1 that you thought was the front straight.

I was at the track a few weeks ago with a 90-ish hp Honda. Well, it was 90-ish hp 35 years ago, it may not be now. This is a track where I spend a lot of time in cars with 500 hp. Did I have more fun in the momentum car? Not really. Did I have less fun? Not really. I enjoyed them both, and I don't know which one I'd take to the next track day. The Honda sure left me in better shape, though - I feel pretty battered after dealing with the high power/weight cars.

It's a different skill set to get the most out of it. Not a better skill set (car guys love to pat themselves on the back for having a crap car for some reason), a different one.

volvoclearinghouse
volvoclearinghouse PowerDork
10/15/20 9:58 a.m.
Keith Tanner said:
frenchyd said:

Please don't tell me you need 700+ horsepower to race.  Maybe your ego does but that's not where the fun is.  

You do if the guys you're racing have 1000+. That's the same equation you had so much fun with, just scaled up. It adds new corners to the track - you don't understand why the Andretti hairpin at Laguna Seca is called "turn 2" until you have some horsepower and you discover the very exhilarating turn 1 that you thought was the front straight.

That's a very good point.  Back to my own experience, racing at CMP, the "Kink" isn't really anything you worry about with a 100-HP car, you simply mash the go juice pedal all the way from corners 8 to 11.  But when you have enough grunt to be doing north of triple-digit speeds by the Kink, some strategy is required or you'll be sideways, backwards, &/or upside down by the time you get to turn 11. 

rustomatic
rustomatic Reader
10/15/20 10:18 a.m.

People like to make this so complicated, which is easy to do with theory.  Put it this way:  A 3000-ish pound car with 340 HP on 225-width tires and a stick axle will feel pretty sprightly at points (like where you're losing grip trying to power out of turns), and quite competent at times (esses/turns in series).  The same-ish car with similar power and a more modern IRS rear (and way better front geo), but with 315-width tires will be a completely different beast where the old setup found quick limits.  This is where it gets possible to have a 400 HP momentum car.

When the chassis is built to specific power limits (or better still, beyond), confidence is more easily and reasonably found.

More power = more fun, but only when the chassis ability corresponds.

maj75 (Forum Supporter)
maj75 (Forum Supporter) HalfDork
10/15/20 11:14 a.m.

You know what's no fun?  Driving your car with one hand because you have to point-by every other car on track with you.  When I started doing track days, the fields had Miata's, E30s, E36s, air cooled Porsche's (for the big tippers), old Vettes or other generally modest cars.  It was fun because it was possible to pass most cars using your driving skills.

Now, folks show up with McLarens, GTRs, Porsche GT2, GT3, GT4, ZR1 Corvettes, ZL1 Camaros, Shelby Mustangs and full on race cars/trucks from sports cars to NASCAR.  If you are still driving your original "momentum car" you spend your whole track time pointing cars by.  Only the most totally inept driver in one of the above cars might get you a pass, but because you are not allowed to pass in the corners, they can pull away on every strait.  It ruins the day for me.  I need enough power to pass on the strait.  I found that 440rwhp in a C5 was enough.  Made a mistake selling the C5, thought I would track my '13 Carrera S, but I chickened out for fear of damaging the car.  Instead, I bought a momentum car, '96 Mustang GT for $3500.  We shall see if I can have fun being a rolling roadblock.

Tom1200
Tom1200 Dork
10/15/20 11:36 a.m.

@Keith Tanner  "car guys love to pat themselves on the back for having a crap car for some reason"  It's that classic case of the wrong side of the tracks versus the townies mentality.

Part of why I like momentum cars is I love dragging a car farther up the order than it has a right to be.

 

 

nderwater
nderwater UltimaDork
10/15/20 11:46 a.m.
maj75 (Forum Supporter) said:

You know what's no fun?  Driving your car with one hand because you have to point-by every other car on track with you. 

LMAO, ain't that the god's honest truth.  

Tom1200
Tom1200 Dork
10/15/20 12:13 p.m.

At the PCA events I do the passing is done on the straights only, so coming off the gas and pointing 3 or 4 cars buy isn't an issue.  At events that have open passing (not a fan of this practice for cars with no safety equipment) that would spoil the fun.

Driven5
Driven5 UltraDork
10/15/20 12:32 p.m.
maj75 (Forum Supporter) said:

Now, folks show up with McLarens, GTRs, Porsche GT2, GT3, GT4, ZR1 Corvettes, ZL1 Camaros, Shelby Mustangs and full on race cars/trucks from sports cars to NASCAR.  

What organization do you run with where those are the majority of entrants? surprise

ProDarwin
ProDarwin MegaDork
10/15/20 12:37 p.m.
Keith Tanner said:

If you have the ability to put down serious acceleration coming out of a corner, you'll run a different line because it allows you to start to accelerate sooner. Giving up 5 mph mid-corner is worth it if you can add 10 mph to your exit speed, because you get that extra speed allll the way to the next braking zone.

So lower power:grip car has an earlier apex than the higher power:grip car?

I'm not fully understanding how - I might need to do the math on this myself.  As shown in the above links (I have no idea what simulation was used), the low power car is still fastest around the corner on the late apex line.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/15/20 12:45 p.m.

I haven't followed the links, but the momentum car is going to want to carry as much speed as possible even if it means less traction available to accelerate, because it doesn't need as much traction to accelerate. The point/shoot car (aka higher power/grip ratio) will want to emphasize the ability to get on the power sooner and prioritize grip for acceleration. So yeah, that sounds like a later apex for the high power/grip car.

I went to a track day at Calabogie with an almost stock 1996 Miata on all-seasons. Now that's a momentum car. I did spend the entire day pointing people by because it turns out that people bring the crazy toys to this series of events. Like a Mercedes GT with a mirror wrap. Had fun for the one or two spots where I could make up ground on the GT3s by being a lunatic, but on the next lap they were long gone...

ShinnyGroove (Forum Supporter)
ShinnyGroove (Forum Supporter) Reader
10/15/20 12:52 p.m.

What I took from that simulation is that late apex is faster for everyone that can accelerate. The less that acceleration is a factor (lower power car, faster turn) the less advatage that you gain from a late apex and the closer you should be to a geometric line. 

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand UberDork
10/15/20 1:27 p.m.
ProDarwin said:
Keith Tanner said:

If you have the ability to put down serious acceleration coming out of a corner, you'll run a different line because it allows you to start to accelerate sooner. Giving up 5 mph mid-corner is worth it if you can add 10 mph to your exit speed, because you get that extra speed allll the way to the next braking zone.

So lower power:grip car has an earlier apex than the higher power:grip car?

I'm not fully understanding how - I might need to do the math on this myself.  As shown in the above links (I have no idea what simulation was used), the low power car is still fastest around the corner on the late apex line.

Different lines through the corner trade off speed in the corner for time at which you can get on the throttle.  Changing the grip and power level will change the optimal tradeoff as far as lap time is concerned.  Length of the straight that comes after will change it as well, but presumably that's the same for both cars.

As for having fun at the track in a car with no power, this is most commonly an issue when you're in the intermediate groups.  Those often include drivers with a wide variety of skill levels, many of whom haven't gotten the "I want to use all 500 hp down every straight" out of their system yet.  Combine that with limited passing rules and it can make for a very frustrating track day.  This situation is why my Miata got its first turbo. :)

As far as ideal "fun" goes, I find that I really prefer track cars to have fewer than 10 pounds per horsepower.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/15/20 1:35 p.m.

I've had a Porsche put on its brakes on the back straight at HPR to let me past in a high grip 150 rwhp ND Miata. Lifting off just wasn't getting the job done. It was pretty funny to see the thought process - point by, lift...brake lights. I did thank him later :)

frenchyd
frenchyd PowerDork
10/15/20 1:59 p.m.
Keith Tanner said:
frenchyd said:

Please don't tell me you need 700+ horsepower to race.  Maybe your ego does but that's not where the fun is.  

You do if the guys you're racing have 1000+. That's the same equation you had so much fun with, just scaled up. It adds new corners to the track - you don't understand why the Andretti hairpin at Laguna Seca is called "turn 2" until you have some horsepower and you discover the very exhilarating turn 1 that you thought was the front straight.

I was at the track a few weeks ago with a 90-ish hp Honda. Well, it was 90-ish hp 35 years ago, it may not be now. This is a track where I spend a lot of time in cars with 500 hp. Did I have more fun in the momentum car? Not really. Did I have less fun? Not really. I enjoyed them both, and I don't know which one I'd take to the next track day. The Honda sure left me in better shape, though - I feel pretty battered after dealing with the high power/weight cars.

It's a different skill set to get the most out of it. Not a better skill set (car guys love to pat themselves on the back for having a crap car for some reason), a different one.

My  Black Jack with 300 horsepower and 2000 pounds could still beat 427 Cobra's.  Aero wise I pushed a lot less air than they did  and I could position myself on the inside of a corner and out brake him from corner entry. 
Once  past, my car got very wide and somehow I was always in front of him under acceleration. When he was nearing his top speed I'd still have a little left since the D type body was really good while the Cobra body shoved a whole lotta air. 
If he'd back off me he could've beat me under acceleration but he couldn't think that way.  He'd follow my taillights into the next corner and when he could stop as quick as I was he'd swerve, get off line and spin out. 
 

The ability to plan your moves quickly is one of the things that can make a slower car beat faster cars. ( that and having your car set up to allow quick changes when they appear. 

Tom1200
Tom1200 Dork
10/15/20 2:01 p.m.

Things I've said at a PCA event during the drivers meeting "your car at half throttle out accelerates my car at full throttle"  "please lift aaaaall the way off the throttle"

As for the earlier apex in a low horsepower car this is two fold; the car may not accelerate fast enough that the car drifts all the way out to the exit kerb and so you start unwinding the wheel sooner to free up the car and use all of the road.

Also one is more likely to rely heavily on trail braking and rotating the car more aggressively will allow you to get away with an earlier apex.

In the Datsun I'm actually thrust vectoring i.e. pointing the car to the inside of the apex kerb, by the time the car actually arrives  at the kerb the car has moved over about a foot.

The picture below best illustrates this: note my hand position on the wheel (almost center with my helmet) and the slip angle of the rear tires. Also note that while I'm at the apex I'm already tracking out toward the exit kerb. The Spitfire behind me is on using a more traditional line and driving style.

 

mazdeuce - Seth
mazdeuce - Seth Mod Squad
10/15/20 2:42 p.m.

I've had corners before in low powered cars where I keep moving the apex back further and further until I can finally carry enough speed that the car is going fast enough to track out properly. This is not a problem that my Corvette driving friends have. 

 

rustomatic
rustomatic Reader
10/15/20 3:07 p.m.

One metric that has been left out (somewhat) is the one that includes style of track.  Some tracks do not really reward horsepower as much as others.  From what I've been told, as an example, Road America has a straight that literally does not end.  From what I've seen, NOLA has something similar, depending on how they've configured it for the day.  From experience, both Laguna Seca and Sonoma can make you feel pretty happy with 350 HP (which is basically low power these days), depending on your skill (and grip) level.  As for my future track, I somewhat fear Road Atlanta, as I'm not sure if my car's brakes are up to task; grip and power will be sufficient, however.

On that note, who here has figured out how to make up time with brakes?  I did a fairly recent ride-along with a friend in a basically stock (Koni struts and track day pads) first-gen RX7 (not remotely poweful), and he did very well in not being passed by far, far faster cars on a track that favored higher horsepower (Thunderhill).  Granted, he would have killed for an LS swap, given less laziness . . .

Tom1200
Tom1200 Dork
10/15/20 3:34 p.m.

Define late braking; for a momentum car it means using less brake force throughout the entire braking process from threshold braking through to trail braking. I believe one of the top driving schools around the country says "brake lighter longer"

Trail braking is probably the most obvious way to make up time on the brakes, which is why I'm such an advocate of learning the technique. Raising the corner entry speed via trail braking also means you don't have to slow down as much

The stereotype for horsepower guys is to roar up to the corner, stand it on the nose (grossly overslowing the car) and then romp the gas pedal. I've had plenty of students in Miatas do the same, so for me it's more of a newbie thing than a horsepower thing.

From an instructor standpoint teaching people to rotate the car via the brake pedal makes a huge difference in lap times. So for me that counts as using the brakes to make up time. 

On the more literal definition of using the brakes to make up time; our D-sports racer pulled 3Gs on the brakes, in that car you literally roared up to a corner impossibly late and stood the car on the nose. The ability to stay on the gas for an extra 150 feet was huge. Because that car had a moderate amount of downforce you didn't need to trail the brakes as long nor rotate it near as aggressively as most other cars.

buzzboy
buzzboy Dork
10/15/20 3:45 p.m.
rustomatic said:

One metric that has been left out (somewhat) is the one that includes style of track.  Some tracks do not really reward horsepower as much as others.  From what I've been told, as an example, Road America has a straight that literally does not end.  From what I've seen, NOLA has something similar, depending on how they've configured it for the day.  From experience, both Laguna Seca and Sonoma can make you feel pretty happy with 350 HP (which is basically low power these days), depending on your skill (and grip) level.  As for my future track, I somewhat fear Road Atlanta, as I'm not sure if my car's brakes are up to task; grip and power will be sufficient, however.

It really is interesting how different cars play so differently with different layouts. Barber and CMP are very similar length tracks, roughly 2.25 miles. Our car on the same setup runs almost identical times at both tracks, both average and hot lap. A friend of ours runs 5-10 seconds slower on average at CMP. CMP is a more flatout track than Barber IME.

Road Atlanta only scares me on the final turn. Coming down under the bridge with that concrete wall in front of you is intimidating. It was relatively easy on brakes for us but we're a VERY momentum based car compared to most.

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand UberDork
10/15/20 4:17 p.m.
Keith Tanner said:

I've had a Porsche put on its brakes on the back straight at HPR to let me past in a high grip 150 rwhp ND Miata. Lifting off just wasn't getting the job done. It was pretty funny to see the thought process - point by, lift...brake lights. I did thank him later :)

Yes, if everyone is polite and paying attention it shouldn't be a problem.  Unfortunately such is often not the case.

What rustomatic says is true, 350 hp is now considered a low power car.  These days I'm driving an E46 M3 on track (one that's minus about 700 pounds from stock weight) and there are days when I feel like it's 20 years ago and I'm back in that stock Miata...

 

frenchyd
frenchyd PowerDork
10/16/20 7:38 a.m.
rustomatic said:

One metric that has been left out (somewhat) is the one that includes style of track.  Some tracks do not really reward horsepower as much as others.  From what I've been told, as an example, Road America has a straight that literally does not end.  From what I've seen, NOLA has something similar, depending on how they've configured it for the day.  From experience, both Laguna Seca and Sonoma can make you feel pretty happy with 350 HP (which is basically low power these days), depending on your skill (and grip) level.  As for my future track, I somewhat fear Road Atlanta, as I'm not sure if my car's brakes are up to task; grip and power will be sufficient, however.

On that note, who here has figured out how to make up time with brakes?  I did a fairly recent ride-along with a friend in a basically stock (Koni struts and track day pads) first-gen RX7 (not remotely poweful), and he did very well in not being passed by far, far faster cars on a track that favored higher horsepower (Thunderhill).  Granted, he would have killed for an LS swap, given less  

Brakes can be used in many ways. Not just to aide a fast lap. But also to gain position. The easiest to understand is if you have similar braking power you can position yourself to the inside as he swings wide to get his best corner speed. You can drive inside him and as you get your nose in front of his then you brake.  Naturally that will carry you deeper into the corner , off line. Now you are in front of him and he cannot accelerate. Yes your lap time will suffer but you have position.  
Another move is the outside pass position yourself to the outside. You are taking away his usual line slowing his corner speed making him brake harder and sooner. 
 

There are variations of both and counter moves 

Just remember position is king. 

volvoclearinghouse
volvoclearinghouse PowerDork
10/16/20 8:05 a.m.

In reply to frenchyd :

Isnt that known as "dive-bombing" ?

grpb
grpb Reader
10/16/20 9:48 a.m.
Keith Tanner said:

If you have the ability to put down serious acceleration coming out of a corner, you'll run a different line because it allows you to start to accelerate sooner. Giving up 5 mph mid-corner is worth it if you can add 10 mph to your exit speed, because you get that extra speed allll the way to the next braking zone.

This right here.  It's all about acceleration, one lap will include a sum of lateral and longitudinal accelerations, but it's much easier to find time with longitudinal acceleration.  The problem with sustained lateral acceleration is that it is the result of constant velocity which means it is a waiting period.  This waiting period is only a benefit if the combination of constant speed and distance of the momentum line between points A and B on the track is quicker than the combination of average speed, including decel and accel, and distance of the shorter point/shoot line between those same points on the track.  Both styles should have the same peak lateral acceleration, but one will sit at that high lat acc for a while (waiting), the other will only briefly touch it before getting back on the gas.

Of course the 'right' way to do it is only right until someone does it a differently and is faster.  Then there is a new 'right' way until the next, etc.

Tom1200
Tom1200 Dork
10/16/20 10:22 a.m.

Volvoclearinghouse, a dive bomb is somebody who magically shows up right at the apex.

What frenchyd is describing is a classic slide job. Done properly the driver doing the pass will have left 1 -2 car lengths of room between the his rear bumper and the other cars front bumper.  (It's the margin I use)  

Done improperly the driver attempting the pass will run slightly wide allowing the other driver to execute the classic over under repass.

The key to executing a proper slide job is your entry speed needs to be 3-4 mph faster than the car being passed, you also need the ability to be able to chuck the car semi-sideways in order to scrub off that extra 3-4 mph to keep yourself from running wide and being repassed. 

80% of amateur drivers do not posses the skill or experience to pull this off. If you try to pull off this maneuver going 1/2 mile per hour faster than the other car, be forewarned it's going to end in tears.

 

 

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/16/20 10:49 a.m.
codrus (Forum Supporter) said:
Keith Tanner said:

I've had a Porsche put on its brakes on the back straight at HPR to let me past in a high grip 150 rwhp ND Miata. Lifting off just wasn't getting the job done. It was pretty funny to see the thought process - point by, lift...brake lights. I did thank him later :)

Yes, if everyone is polite and paying attention it shouldn't be a problem.  Unfortunately such is often not the case.

What rustomatic says is true, 350 hp is now considered a low power car.  These days I'm driving an E46 M3 on track (one that's minus about 700 pounds from stock weight) and there are days when I feel like it's 20 years ago and I'm back in that stock Miata...

 

We did have a good laugh about it later.

There is a dramatic difference between driver behavior at Californian and Colorado track days. It's easier to drive an outlier car in Colorado in my experience.  There's also quite a difference in the cars - at the HPR days I frequent, I'm more likely to see a race-prepped 510 (talk about a momentum car!) than a 911. 

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/16/20 11:37 a.m.

I've noticed that this discussion seems to be equating "momentum car" with "slow" and then it turns into self-proclaimed hero stories. I'm guilty of the former at the very least.

But that's not necessarily the case. Momentum cars just have their speed in different places. They can't accelerate as well as they can corner.  You see this decision in F1 occasionally where a mid-pack team decides to go with a wild downforce setup to give them a distinct difference in the grip/power ratio than the rest of the pack. Usually it involves low downforce so the car is less of a momentum car and can thus use greater straight line speed to pass/defend. There aren't many series where you can  adjust grip vs speed like this, but F1's aero does make it possible. 

A "momentum cars aren't slow" example. Minis were a dominating force back in the 60s and they're certainly not a point-and-shoot kind of car. Let's take the 500 mile Bathurst race at Mount Panorama in 1966. The Mountain is very much a power track, with a big climb up one side and a long, long, long straight on the flat - this was back before the chicane was added. It's pretty difficult to pass on the downhill section, most of the passing seems to happen on the long straight or the braking zones before the climb up the hill. Minis took the top 9 spots in the race, with V8-powered Valiants coming in 10-11. This was not an example of the Mini drivers putting their weak little cars where they don't belong, it was a triumph of handling over horsepower.

We saw momentum over horsepower play out over and over in endurance racing in the 60s. If I remember correctly, the 250 GTO would win on the handling tracks (a V12 Ferrari playing the role of the momentum car!) and the Cobra would win on the high power tracks. This doesn't mean the Ferrari drivers were better, simply that it was a better tool for some tracks and worse for others.

CAinCA
CAinCA GRM+ Memberand Reader
10/16/20 1:29 p.m.
Keith Tanner said:

There is a dramatic difference between driver behavior at Californian and Colorado track days. It's easier to drive an outlier car in Colorado in my experience.  There's also quite a difference in the cars - at the HPR days I frequent, I'm more likely to see a race-prepped 510 (talk about a momentum car!) than a 911. 

I've been to Laguna Seca 6-7 times in the last year and a half. Every time there are guys with $50k-$100k cars that have no business driving them. With the Silicon Valley nearby there are a lot of people that are suddenly well off but have very little driving experience. In my 220hp GTI I've passed 911s, Caymans, Elises, Corvettes, Teslas, Alfa Romeo Giulias, BWMs, etc. As I've moved up the ladder the drivers seem to be more aware and courteous. I'm hoping that by the time I get into the groups requiring 10+ track days that the driving will be better. I wish they would break up the groups by lap times. 

Tom1200
Tom1200 Dork
10/16/20 1:46 p.m.

Keith on the subject of Minis,

 They are around 1400lb with driver and putting 115-120hp to the wheels, which equates to around a 13 second 1/4 mile. So while they are not fast they are also not slow, they are in the same run group as me at vintage races so I am familiar with them.

Your point about momentum cars not necessarily being slow is well taken, Formula Atlantic  & F3 cars are fast but they are still momentum cars. 

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/16/20 1:46 p.m.

The groups are split up by driver skill so that the rules for each group can be adjusted accordingly. You don't want a novice in a hypercar being allowed to pass in corners, no matter what the lap time. And you don't need to limit a top level Spec Miata driver to point-by hell just because their car does not actually possess the power of acceleration.

Your 200 hp GTi passing Caymans is not a momentum car issue, it's a skill level issue. That's completely different.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/16/20 1:53 p.m.
Tom1200 said:

Keith on the subject of Minis,

 They are around 1400lb with driver and putting 115-120hp to the wheels, which equates to around a 13 second 1/4 mile. So while they are not fast they are also not slow, they are in the same run group as me at vintage races so I am familiar with them.

Your point about momentum cars not necessarily being slow is well taken, Formula Atlantic  & F3 cars are fast but they are still momentum cars. 

I have a classic Mini that I've taken on track. It has very good cornering ability relative to its acceleration ability which makes it a textbook example of a momentum car. There are places where other cars hit the brakes and I shift into the next gear, but it takes me a lap to get up to speed :) 

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand UberDork
10/16/20 1:58 p.m.
CAinCA said:
Keith Tanner said:

There is a dramatic difference between driver behavior at Californian and Colorado track days. It's easier to drive an outlier car in Colorado in my experience.  There's also quite a difference in the cars - at the HPR days I frequent, I'm more likely to see a race-prepped 510 (talk about a momentum car!) than a 911. 

I've been to Laguna Seca 6-7 times in the last year and a half. Every time there are guys with $50k-$100k cars that have no business driving them. With the Silicon Valley nearby there are a lot of people that are suddenly well off but have very little driving experience. In my 220hp GTI I've passed 911s, Caymans, Elises, Corvettes, Teslas, Alfa Romeo Giulias, BWMs, etc. As I've moved up the ladder the drivers seem to be more aware and courteous. I'm hoping that by the time I get into the groups requiring 10+ track days that the driving will be better. I wish they would break up the groups by lap times. 

Broadly speaking, yes, the more advanced groups tend to be better in terms of awareness.  Intermediate groups are the worst in that regard, in my experience.

What track day organizations are you going with?  Laguna is a bit of an odd case, it's definitely a horsepower track and the sound rules mean that lots of people are driving strangely.  This is particularly noticable at high-db days where you'll get a bunch of people showing up with fast cars but very little experience there.

As for lap time divisions, as Keith says that's mostly a safety thing.  That said, organizations with multiple advanced/open groups will sometimes split them by lap time.

Tom1200
Tom1200 Dork
10/16/20 3:32 p.m.

Kieth you probably know this already but your classic Mini and a vintage race prepped Mini are worlds apart.

So when I raced motorcycles practice was separated out by lap times; this worked well because there was open passing and you don't end up with the issues one has at track days.

As for track days; I run the F500 in the advanced group and the Datsun (due to how slow it is) in the intermediate group. The issue with the intermediate group is that a portion of the drivers are experienced enough to get their car up to speed but they don't yet have the capacity to drive at speed and be aware of their surroundings. Additionally some of the same drivers may be at a level where they now posses just enough skill to get themselves into trouble but lack the skill to get themselves out of trouble.

Note I am an advocate of people starting out in momentum cars.

CAinCA
CAinCA GRM+ Memberand Reader
10/16/20 3:54 p.m.
Keith Tanner said:

The groups are split up by driver skill so that the rules for each group can be adjusted accordingly. You don't want a novice in a hypercar being allowed to pass in corners, no matter what the lap time. And you don't need to limit a top level Spec Miata driver to point-by hell just because their car does not actually possess the power of acceleration.

Your 200 hp GTi passing Caymans is not a momentum car issue, it's a skill level issue. That's completely different.

I guess I misunderstood your post above. I thought I was agreeing with it. What dramatic difference do you see between CA drivers and CO drivers?

CAinCA
CAinCA GRM+ Memberand Reader
10/16/20 4:10 p.m.
codrus (Forum Supporter) said:
CAinCA said:
Keith Tanner said:

There is a dramatic difference between driver behavior at Californian and Colorado track days. It's easier to drive an outlier car in Colorado in my experience.  There's also quite a difference in the cars - at the HPR days I frequent, I'm more likely to see a race-prepped 510 (talk about a momentum car!) than a 911. 

I've been to Laguna Seca 6-7 times in the last year and a half. Every time there are guys with $50k-$100k cars that have no business driving them. With the Silicon Valley nearby there are a lot of people that are suddenly well off but have very little driving experience. In my 220hp GTI I've passed 911s, Caymans, Elises, Corvettes, Teslas, Alfa Romeo Giulias, BWMs, etc. As I've moved up the ladder the drivers seem to be more aware and courteous. I'm hoping that by the time I get into the groups requiring 10+ track days that the driving will be better. I wish they would break up the groups by lap times. 

Broadly speaking, yes, the more advanced groups tend to be better in terms of awareness.  Intermediate groups are the worst in that regard, in my experience.

What track day organizations are you going with?  Laguna is a bit of an odd case, it's definitely a horsepower track and the sound rules mean that lots of people are driving strangely.  This is particularly noticable at high-db days where you'll get a bunch of people showing up with fast cars but very little experience there.

As for lap time divisions, as Keith says that's mostly a safety thing.  That said, organizations with multiple advanced/open groups will sometimes split them by lap time.

So far I've run with SpeedSF and NCRC. The problems I've seen are probably at least partially due to COVID since the instructors can't go out with anyone. I've had people stab their brakes mid corner, point me by where they shouldn't have, or just plain refuse to let me by even though I was clearly faster. On the GTI forum it's been mentioned a few times that guys can not stand to let a $30k E36 M3 box pass their $60k dream car.

I understand WHY they break up the groups the way they do. I just wish I could run in a group of cars and drivers that all had similar lap times to me. I've had a blast chasing a C6 Corvette and Mustang GT that were running similar lap times. I've also had a blast running with a Focus ST and Works Mini. 

Anyway, this should be a separate thread.

rustomatic
rustomatic Reader
10/16/20 4:57 p.m.

In reply to Tom1200 :

Your last example here is what I meant to point out regarding the friend in the RX7.  He would literally wait until he was in the corner, aiming for a late apex, then slam brakes (hard) only enough to set and get.  He'd refined this process doing Lemons races for hours at a time.  It was hysterical, and I think I had some seatbelt marks after, but it was an effective approach that I never considered.  I've always just preferred doing everything but braking (momentum on the brain), but needs change when you can get those higher speeds in the straighter sections.  Karting can teach endless great lessons here.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
10/16/20 5:11 p.m.
CAinCA said:
Keith Tanner said:

The groups are split up by driver skill so that the rules for each group can be adjusted accordingly. You don't want a novice in a hypercar being allowed to pass in corners, no matter what the lap time. And you don't need to limit a top level Spec Miata driver to point-by hell just because their car does not actually possess the power of acceleration.

Your 200 hp GTi passing Caymans is not a momentum car issue, it's a skill level issue. That's completely different.

I guess I misunderstood your post above. I thought I was agreeing with it. What dramatic difference do you see between CA drivers and CO drivers?

Aggressiveness and ego. People don't win track days in CO and will give up a corner instead of putting themselves in a sketchy situation. Basically, drivers work together more. CA track day drivers seem to think they're racing and will be much more aggressive in order to come out ahead so they can claim the big prize. I've never won it myself so I don't know what it looks like, but it must be nice.

Obviously, this is a gross generalization. But it's prevalent enough that I do have to adjust my driving and the way I expect other drivers to move when I travel from CO to CA and back again.

As for the Porsche-killing 200 hp GTi - put the same driver in both cars, the Cayman/911/Tesla/whatever will likely be faster. You expect that to be the case which is why you called them out. So you're not passing them because you're a momentum car and they're not or vice versa, you're passing them because you have a higher skill level. Turn the tables and you wouldn't. That's got nothing to do with momentum cars.

Again, people are equating "momentum" with "slow". And "horsepower" with "fast". That's not true. It takes a certain type of skill to take full advantage of a car with a high power/grip ratio, and a different type of skill to take full avantage of a car with a low power/grip ratio. Those skills do transfer, so you can learn things in one type of car that you won't learn with another. A high power/grip car (aka point and shoot) will teach you a lot about throttle modulation and how to dance on the edge of the traction circle on corner exit. The throttle pedal isn't just a binary switch, it's a sensitive rheostat. It'll also teach you more about significant braking events. The low power/grip car (momentum) will teach you about how to maintain cornering speed and maximizing corner entry speed and drafting and velocity is precious so don't let it leak away - but it won't teach you much about throttle control because, well, the answer is probably "all of it" most of the time.

I know my fast road Mini is not a race Mini. But I don't expect they're radically different. And in my Mini example, they were racing against full-size family saloons with big horkin' V8s. You're not going to tell me that the Mini isn't the momentum car in that situation.

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand UberDork
10/16/20 5:27 p.m.
CAinCA said:

So far I've run with SpeedSF and NCRC. The problems I've seen are probably at least partially due to COVID since the instructors can't go out with anyone. I've had people stab their brakes mid corner, point me by where they shouldn't have, or just plain refuse to let me by even though I was clearly faster. On the GTI forum it's been mentioned a few times that guys can not stand to let a $30k E36 M3 box pass their $60k dream car.

I am not a fan of SpeedSF.  NCRC's open/advanced group is usually pretty polite, can't speak to the intermediates.

You might consider Hooked On Driving -- their events are more expensive, but folks there are usually quite well-behaved in this sort of situation.

 

Tom1200
Tom1200 Dork
10/16/20 5:42 p.m.

Keith agreed both fast road Mini and race Mini are momentum cars but the race Mini is closer to the big V8 Holden in the slower corners than people think...........once the speed increases the standard Mini body is pretty much a parachute.  I've watched Minis out drag Spec Boxsters on race starts.

As for not learning throttle control in a low power car I disagree; in a low power car if you get on the throttle to hard to early you will end up with loads of speed scrubbing understeer.  So just like something with the ability to spin the tires one has to wind on the throttle progressively.

JFRCross88
JFRCross88 New Reader
10/19/20 4:05 p.m.

Great column and I am in agreement. I prefer balanced cars that handle well, especially on the street. Before I raced, I did track days and autocross. During those early track days in my normally aspirated 4's, it was interesting to get passed or gapped by high horsepower cars after corners, but catch up to them upon entry and be held up in the corner. For me driving a momentum car is more fun. My SCCA ITA car was an 87 Civic Si, momentum. For street driving 200-250 hp is plenty for me and does not leave me wanting more. 

All that said, we are all different and it's great that there enough choices out there so that we can drive what we like. 

cck
cck New Reader
8/2/21 5:22 p.m.
codrus (Forum Supporter) said:
CAinCA said:

So far I've run with SpeedSF and NCRC. The problems I've seen are probably at least partially due to COVID since the instructors can't go out with anyone. I've had people stab their brakes mid corner, point me by where they shouldn't have, or just plain refuse to let me by even though I was clearly faster. On the GTI forum it's been mentioned a few times that guys can not stand to let a $30k E36 M3 box pass their $60k dream car.

I am not a fan of SpeedSF.  NCRC's open/advanced group is usually pretty polite, can't speak to the intermediates.

You might consider Hooked On Driving -- their events are more expensive, but folks there are usually quite well-behaved in this sort of situation.

 

I have run with HOD (5 x) , speedsf, NCRC, trackmasters and GGLC. Agree HOD are best organized and drivers are generally polite. I really like GGLC as well, very friendly drivers and "momentum" oriented.

Cactus
Cactus HalfDork
8/3/21 12:03 a.m.

Thread back from the grave!

One thing I've noticed is that the bread and butter cars are a lot faster these days than they were when I started HPDEs. Golf Rs and regular Camaro SSs have an awful lot of power and tire on non M3 E36s/46s and first gen Caymans. I miss the days when 200hp was plenty, and 300 was a lot. Not that you can't still have fun with that, but the goalposts have moved a long way.

Occasionally you'd see some eccentric in a Ferrari Challenge car or something, so I'm not sure the pointy end is much sharper, but the average machine is way up from my youth.

frenchyd
frenchyd UltimaDork
8/3/21 7:59 a.m.
volvoclearinghouse said:

In reply to frenchyd :

Isnt that known as "dive-bombing" ?

Since there are counters to dive bombing  and a skilled driving can see the set up. It's just a technique. Sometimes people fail to use their mirrors  and are surprised by the move.  That's why when it's used in Vintage racing you need to know who you're racing with. Because of the 13/13 rile. No Contact
   In the end the first car to cross the finish line wins.   
     With less horsepower you can tuck in behind the more powerful car and have him pull you down the straight. Yes that's tailgating but permitted. As is "divebombing" 

ShinnyGroove (Forum Supporter)
ShinnyGroove (Forum Supporter) HalfDork
8/3/21 3:58 p.m.

I know this is a zombie thread that just came back to the top, but I've been thinking about it.  Keith's post about power/grip ratio and how it changes the racing line "feels" right but I can't conceptualize why.  So thinking like an engineer, what are the boundary conditions?

Boundary condition #1:  All grip, no power.

This one seems pretty simple.  Assume you are in a soapbox derby car with rubber tires and brakes but no motor, and you have to navigate a race turn.  The fastest line through the turn will always be max cornering speed on the "geometric" line- constant turn radius, no early or late apex.  It's fastest because it's the shortest distance around the corner, and it maintains the largest turn radius possible without ever requiring a tighter radius that would scrub speed.

Boundary condition #2: All power, no grip.

Harder to conceptualize, because there has to be some amount of grip or you can't turn at all.  In fact, you can't have power without grip either, so this boundary doesn't really exist.  So the boundary condition here is a car that has exactly the amount of power needed to break the tires loose at all RPM's. 

Based on boundary condition #1, we know that any deviation from the geometric line is going to cost time by either covering more distance or scrubbing speed.  The friction circle dictates that the tires only have so much grip; any grip you use to accelerate will come at the expense of lateral grip and thus cornering speed.  By deviating from the geometric line, you are decelerating to make a tighter turn somewhere, so you can make a looser turn somewhere else to accelerate.  The bet you're making is that the magnitude of acceleration is greater than the magnitude of the deceleration.  This seems like it violates some fundamental law of nature to me; the total amount of grip is finite, and is the only limiting factor for corner speed AND acceleration.

In real life nothing is linear or perfect (least of all drivers) and accommodations need to be made.  However, this logic still strongly suggests to me that the comment "every car is a momentum car" is correct in principle.  Somebody tell me what I'm missing?

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
8/3/21 5:11 p.m.

You're assuming that a lower power/grip car has enough acceleration available to exhaust available traction :) You're also forgetting what happens after the corner.

With the high power/grip car, the earlier you can accelerate the more speed you'll have down the straight. If you can give up 3 mph mid-corner by taking a less-than-ideal line, but gain 5 mph by the time you get to corner exit, you benefit. So it's worth squaring off the corner somewhat in that case, you're setting yourself up to apply that traction longitudinally as soon as possible. Your total time in the corner may be longer but your time on the straight will be less.

Same thing happens to some extent on corner entry.

I'm lucky to have access to very similar cars with radically different power/grip ratios. I definitely have to adjust my lines to get the best lap times, and it's more obvious on some cars than others. In one case - a chicane exit - it's worth taking a line that goes diagonally across the track in the high power/grip because I can get on the power sooner and longer. In a car with the same suspension and tires but half the power, I take a more arcing line to maintain as much speed as possible down the short straight. My line through the chicane is almost identical because there's no way to deploy the power anyway.

Of course, it's not black and white. As noted, it's relative. And as soon as you're trying to deal with another car mid-corner, the rules change :)

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand PowerDork
8/3/21 5:32 p.m.

The other thing you're missing is that by taking a larger radius you're travelling a longer distance.  Yes, you're travelling at a higher speed for that distance, but it's not necessarily enough to make up for the time.  The wider corner radius gives you a higher exit speed at the cost of more time in the corner, the idea being that the higher exit speed will translate into less time spent in the next straight.  The longer the following straight the more this tradeoff is worth it, which is why "hugging the inside" at autox is sometimes worthwhile when there's little-to-no straight after a corner.

The other thing that affects this tradeoff is the amount of power you have in the car.  The more spare horsepower you have the less you need those bonus mph on exit, so with enough power it becomes worthwhile to take a smaller radius through the corner in order to minimize the time spent cornering and get on the power sooner.

One argument for the definition of a "momentum car" is one where you're very rarely (never?) making a choice to sacrifice exit speed to favor earlier throttle application.

 

Tom1200
Tom1200 SuperDork
8/3/21 7:34 p.m.

In reply to codrus (Forum Supporter) :

I've always differentiated the two this way.

If you are focusing on getting the maximum grip for all four tires at once, you are in a momentum car.

If you are focusing on foward bite / getting the car up on the rear tires you are not in a momentum car.

rustomatic
rustomatic Reader
10/7/21 11:38 a.m.

Okay, try this one:  Find a kart rental that has the standard B-S L0206 which makes sub-10 hp.  You can have a good time with that, especially on a tighter track, or on one that's opened up enough to where you barely brake at all (momentum, yo).  Then, see if somebody will let you drive a kart with 50 hp.

See how using those pedals makes you feel now?  The difference is massive, and reasonably, many would rather stick with the sub-10 hp kart . . .

Being reasonable severely limits the availability of fun.

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
10/7/21 12:15 p.m.
codrus (Forum Supporter) said:

The other thing you're missing is that by taking a larger radius you're travelling a longer distance.  Yes, you're travelling at a higher speed for that distance, but it's not necessarily enough to make up for the time.  The wider corner radius gives you a higher exit speed at the cost of more time in the corner, the idea being that the higher exit speed will translate into less time spent in the next straight.  The longer the following straight the more this tradeoff is worth it, which is why "hugging the inside" at autox is sometimes worthwhile when there's little-to-no straight after a corner.

The other thing that affects this tradeoff is the amount of power you have in the car.  The more spare horsepower you have the less you need those bonus mph on exit, so with enough power it becomes worthwhile to take a smaller radius through the corner in order to minimize the time spent cornering and get on the power sooner.

One argument for the definition of a "momentum car" is one where you're very rarely (never?) making a choice to sacrifice exit speed to favor earlier throttle application.

 

 

A larger radius requires less maintenance power.

I recall many times taking corners in the widest possible arc in my Quantum at WOT and still slowing down from 75 to 65 by corner's end, because cornering took away more speed than I could maintain.

I know I am not a good driver, because I'm sure there was a way to maximize corner exit speed, and I couldn't seem to find it.

malibuguy
malibuguy GRM+ Memberand HalfDork
10/8/21 7:15 a.m.

I just got my 1nz swap into a Tercel done.  Granted it makes less HP then the motor that it replaced which was heavily turbocharged (106 vs 175)...yet going thru a 4speed automatic.

However with the swap along with the motor came the matching 4.31 final drive 5speed that came mated with it in Scions.

Compared to my other Tercel which has a mild turbo set up and 3.72s its nearly as quick in the 40-70 sprint that I like to measure cars HP in on a local level road.

A lot of people have already said to me "I cant wait for you to boost it" referencing the swapped Tercel.  And I loosely had that planned in the back of my head.  But after driving it some.  Its like spot on as is.  I still need to refine the car, replace the clutch and some other do-dads.  The car is not built for competition (tho I will probably take it to the drags and autoX eventually for fun) its primary purpose is a mountain therapy car.

Beer Baron
Beer Baron MegaDork
1/13/22 10:01 a.m.

On the road, every car goes effectively the same speed.

On the track, fast cars train slow drivers.

Shaun
Shaun GRM+ Memberand Dork
1/13/22 12:18 p.m.
frenchyd said:
rustomatic said:

One metric that has been left out (somewhat) is the one that includes style of track.  Some tracks do not really reward horsepower as much as others.  From what I've been told, as an example, Road America has a straight that literally does not end.  From what I've seen, NOLA has something similar, depending on how they've configured it for the day.  From experience, both Laguna Seca and Sonoma can make you feel pretty happy with 350 HP (which is basically low power these days), depending on your skill (and grip) level.  As for my future track, I somewhat fear Road Atlanta, as I'm not sure if my car's brakes are up to task; grip and power will be sufficient, however.

On that note, who here has figured out how to make up time with brakes?  I did a fairly recent ride-along with a friend in a basically stock (Koni struts and track day pads) first-gen RX7 (not remotely poweful), and he did very well in not being passed by far, far faster cars on a track that favored higher horsepower (Thunderhill).  Granted, he would have killed for an LS swap, given less  

Brakes can be used in many ways. Not just to aide a fast lap. But also to gain position. The easiest to understand is if you have similar braking power you can position yourself to the inside as he swings wide to get his best corner speed. You can drive inside him and as you get your nose in front of his then you brake.  Naturally that will carry you deeper into the corner , off line. Now you are in front of him and he cannot accelerate. Yes your lap time will suffer but you have position.  
Another move is the outside pass position yourself to the outside. You are taking away his usual line slowing his corner speed making him brake harder and sooner. 
 

There are variations of both and counter moves 

Just remember position is king. 

Max agrees!!

MrFancypants
MrFancypants HalfDork
1/13/22 3:20 p.m.

As a semi-competent amateur HPDE warrior my view on this is pretty simple and comes down to $/event.

Aside from certain modified or exotic cars big horsepower tends to come with extra weight, big horsepower and extra weight leads to more heat, extra weight and more heat needs more brake and more tire, more brake and more tire means more $$$ per session.

Because of that I prefer sub 3000 lb cars for track days to maximize my track time per dollar spent, and typically these cars don't exceed 250 hp. I suppose these are regarded as "momentum" cars.

Big horsepower on the street can be fun because ripping it up to or just over freeway speeds doesn't cost so much extra that it's a problem. Buy the right car and it might not even be too far off the fuel efficiency of smaller lighter cars that it's even noticeable at the pump. But for a track junkie the costs can really add up.

trucke
trucke SuperDork
1/13/22 5:06 p.m.

Low HP cars can be a hoot when setup properly.  You can hoon all day under the speed limits and have a fantastic time!  Now I have a Civic Type R to be competitive in autocross and having to learn to manage a bunch of new and different variables. 

This year my oldest daughter wants to autocross so we will co-drive my older autocross toy.........

 

docwyte
docwyte PowerDork
1/13/22 5:11 p.m.

Low HP cars at a DE/Track event suck.  #1 I'm simply not entertained by them.  Going slow, is well, slow and not fun.  #2  It's simply not a fun time constantly watching your mirrors and sticking your arm out the window giving the pass sign.

It's one thing to be racing with a group of cars that all have the same HP/LBS ratio, it's another situation entirely to have 1/2 the HP of everyone else in the group.  That gets really old, really, really fast.

Tom1200
Tom1200 UltraDork
1/13/22 6:40 p.m.

In reply to docwyte :

Although I've replied in this thread ad nauseam I will add some comments; If you're not entertained by low power cars I get it, my son drove his Lexus at his first track day rather than my Datsun. 

Being in a low powered car doesn't mean you are going slow. 

At a track day earlier this month I was asked to run in the advanced group (we need to free up space in other groups). The Datsun currently has the back up motor which makes 80whp. The event allowed point by anywhere; this was not a big deal.  You simply point someone by when it works for you.............it's not a race so you are not holding up any leaders. It's pretty easy to see when and where someone is going to catch up to you.

If you are in an intermediate to advanced driver you should able to drive the car on the limit and keep track of what's behind you (my personal opinion).

I'm only commenting because there seems to be a widely held belief that if you bring a slow car your going to spend your whole day trying to stay out of the way...........which is not accurate.

 

 

  

RWP
RWP New Reader
1/13/22 7:05 p.m.

Great article and very accurate.  Momentum cars I've had and liked include 88 MR2, 99 Miata, 82 Scirocco (82 hp), 91 Mazda Protege.  All handled and stopped above their class.  140 was the most HP of any of them.  Just bought an 86 944....<150 HP.

maj75 (Forum Supporter)
maj75 (Forum Supporter) Dork
1/13/22 8:21 p.m.
Tom1200 said:

In reply to docwyte 

I'm only commenting because there seems to be a widely held belief that if you bring a slow car your going to spend your whole day trying to stay out of the way...........which is not accurate.

Only true if the drivers in the fast cars suck.  And even if the suck, they will still be ahead of you because they pull away on every straight.  Given equal or better drivers, you will be the slow car giving point by's all day and that's the truth.

Tom1200
Tom1200 UltraDork
1/13/22 8:52 p.m.
maj75 (Forum Supporter) said:
Tom1200 said:

In reply to docwyte 

I'm only commenting because there seems to be a widely held belief that if you bring a slow car your going to spend your whole day trying to stay out of the way...........which is not accurate.

Only true if the drivers in the fast cars suck.  And even if the suck, they will still be ahead of you because they pull away on every straight.  Given equal or better drivers, you will be the slow car giving point by's all day and that's the truth.

Yes, but point bys are not that big of a deal. People act like you have to pull over to the side of the track.

Spec Miata guys give each other hand signals mid corner all the time..........pointing someone by is the exact same thing.

Again pointing people by isn't a big deal, no clue why people think it is.

​​​​​​

 

frenchyd
frenchyd UltimaDork
1/13/22 10:10 p.m.

In reply to Tom1200 :

Point by's suck if you don't have anybody to dice with.   I can have a lot of fun pointing others by if I can beat them in corners. Or there are others about my speed.  
 But if I'm tail end Charlie and All I'm doing is driving it's no fun at all.   
      Maybe a newbie can get satisfaction out of doing by himself if his lap times improve. Or he can sort out the car etc. but wheel to wheel racing isn't like track days. 
   By the way that applies to fast cars too.  Running away from the field is boring.  It's not really racing. It's just driving fast 

MrFancypants
MrFancypants HalfDork
1/13/22 10:20 p.m.
maj75 (Forum Supporter) said:
Tom1200 said:

In reply to docwyte 

I'm only commenting because there seems to be a widely held belief that if you bring a slow car your going to spend your whole day trying to stay out of the way...........which is not accurate.

Only true if the drivers in the fast cars suck.  And even if the suck, they will still be ahead of you because they pull away on every straight.  Given equal or better drivers, you will be the slow car giving point by's all day and that's the truth.

I've been the guy in the fastest car doing the fastest times on track and I've been the guy in one of the slower cars on track. You know what's more frustrating than giving point bys? Spending most of the session behind slower cars waiting for your point by.

I'll happily enjoy watching a Corvette or GT-R scream off into the horizon from behind the wheel of a stock Miata after I point them by, it's a lot more fun than being never being able to get a fast lap in.

Tom1200
Tom1200 UltraDork
1/13/22 10:24 p.m.

In reply to frenchyd :

Track days are not racing. Their sole purpose is to simply allow one to drive their car faster than they could on the road. 

I have made the statement that I'd be perfectly content to drive on an empty track as I enjoy driving fast.

I enjoy wheel to wheel racing more but I still enjoy driving fast, much in the same way I enjoy riding my dirt bike. I ride fast enough to be fun but slow enough to come back in one piece.

350z247
350z247 Reader
1/14/22 8:21 a.m.

In reply to Tom1200 :

Nah, I'm with the others on this one. Spending the entire sessions giving point-bys to Corvettes and Camaros really ruins the session for me. I don't need to be the fastest car on track, but I definitely don't want to be the slowest.

docwyte
docwyte PowerDork
1/14/22 10:47 a.m.

In reply to Tom1200 :

Sorry but that's inaccurate.  In the high run groups, having say a miata, with 1/4 to 1/5th the HP of everyone else makes you a rolling chicane.  I don't care how good of a driver you are, because everyone else in that group is pretty damn good too.

Since those groups tend to have open passing, you constantly have to be scanning your mirrors for the traffic come up on you like a cruise missile, figuring out where to let them by and pointing them by.

Again, and again and again for the entire session.  Nope.  Not fun, not in the least.  Overcoming a certain amount of a HP deficit with skill can be fun but when you're just so vastly out gunned and everyone in the group is a pretty damn good driver, that's no longer fun

Tom1200
Tom1200 UltraDork
1/14/22 3:17 p.m.

In reply to docwyte :

So here is where I'm at; I can 4 wheel drift my car from entrance to exit and wave people past at the same time.....so for me it's not a big deal. I'm not alone in this. Watch in car video of Spec Miata guys, they're sliding through corners and using hand signals. For a decent driver it's not that hard.

Additionally if you put a little bit of forethought into passing, this goes for the fastest and slowest cars in the group, it makes it even less of an issue.

Also note I typically run in the intermediate group which is a better fit but running in the advanced group wasn't a big deal.

I'm not advocating people run out and get a car as slow as my Datsun or run a slow car in the advanced group. I'm just saying with the right attitude and some planning it's not a big deal. 

 

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
1/14/22 3:41 p.m.

In reply to 350z247 :

I never minded giving point by to people in Vipers and 911s but it was frustrating as all hell when they would want a point by and then baby their cars around the corners where passing isn't allowed.

Maybe suck it up for a lap and then I'll walk away from you enough that you won't come up to me at the end of the straight.

AnthonyGS (Forum Supporter)
AnthonyGS (Forum Supporter) SuperDork
1/14/22 4:54 p.m.

Worry about everyone in a faster car and not wanting a slower car costs $$$ and takes a lot of fun out of motor sports.  
 

In the early 00s, I saw a spec Miata keeping up with a Viper GTS at Portland Intl.  Sure tye Vioer win the front straight but every lap the Miata would catch up again before the straight.  
 

On any track day, there will be a variety of capabilities car and driver wise.  You can either adapt, or you cannot.  Attitude is a big part of that.  

350z247
350z247 Reader
1/14/22 6:01 p.m.

In reply to AnthonyGS (Forum Supporter) :

Can we get a proof read and some grammar? That first sentence is a doozy.

Tom1200
Tom1200 UltraDork
1/14/22 6:14 p.m.

In reply to 350z247 :

Grammer.......it's the internet, we don't need no stinking grammer

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand PowerDork
1/14/22 6:46 p.m.
AnthonyGS (Forum Supporter) said:

In the early 00s, I saw a spec Miata keeping up with a Viper GTS at Portland Intl.  Sure tye Vioer win the front straight but every lap the Miata would catch up again before the straight.  

The guy in the Viper didn't know how to drive.  Put an equal driver in the Viper and the Miata driver will never seen him again -- at least, not until he comes up to lap you. :)

Personally I find track days a lot more rewarding when the traffic in the group is mostly running at the same speed and thus minimizing the number of passes that need to happen and it has nothing to do with "winning the track day".  When I'm at the track I'm not just driving in circles for fun, I'm there with a set of goals in mind.  Perhaps I'm trying to set a particular lap time, refine my lines through various corners, or maybe just work on various parts of my driving.  Improved braking techniques, carrying more speed, better throttle modulation, etc.  Doing those things takes mental energy, concentration, and focus.

Safely managing passing ALSO takes some of that energy.  In a perfect world I'd have the track to myself and could devote all of my attention to my own driving.  In the real world I'm sharing the track with other people, passes are a fact of life and I need to divert energy to them.  The more often that happens, the less time I can devote my full attention to achieving my personal goals.  It's not just the actual pass either -- I'm planning it out for several corners before it happens, and then once it's over it takes some time to get my brain back into "the zone".  This is true whether I'm the faster OR slower car, it may be the responsibility of the passing car to make sure it happens safely, but that doesn't mean the driver of the slower car can shut his brain off.  Making passes happen smoothly at track days is a cooperative exercise.

Once a track day goes beyond 2 or maybe 3 passes a lap, the overhead of managing those passes quickly starts to dominate and I'm not making progress on my goals.  Again this applies whether I'm the faster OR slower car.  Bringing a car that's, say, 10-20 seconds a lap slower than the average pace of the group is a recipe for frustration.

 

frenchyd
frenchyd UltimaDork
1/14/22 6:48 p.m.
MrFancypants said:

As a semi-competent amateur HPDE warrior my view on this is pretty simple and comes down to $/event.

Aside from certain modified or exotic cars big horsepower tends to come with extra weight, big horsepower and extra weight leads to more heat, extra weight and more heat needs more brake and more tire, more brake and more tire means more $$$ per session.

Because of that I prefer sub 3000 lb cars for track days to maximize my track time per dollar spent, and typically these cars don't exceed 250 hp. I suppose these are regarded as "momentum" cars.

Big horsepower on the street can be fun because ripping it up to or just over freeway speeds doesn't cost so much extra that it's a problem. Buy the right car and it might not even be too far off the fuel efficiency of smaller lighter cars that it's even noticeable at the pump. But for a track junkie the costs can really add up.

 There are plenty of exceptions to your  sub 3000# 250 hp rule. 
   Assuming you have mechanical skills.   I'll point out only what I know a lot about , the Jaguar XJS V12  can get under 3000# and over 400 hp  by careful shopping you can do that for under $2000. 
     Same with the simpler XJS 6 cylinder. 
  Possible to be at 2500 # with 450 hp for only about $500 more. 
     I know other Jaguars are the same sort of deal. ( no personal experience  though)   
      The reason I push Jaguars is most of them seem to be owned by poseur's. Thus the mechanical stuff is overbuilt and not worn out. 
  I wonder if there are similar Mercedes Benz deals?  It would seem that there are a whole bunch of poseur's who own those and I know how silly expensive service work is on them. Which means heavy depreciation.  
  As far as consumables go though. Tires and brakes should be affordable especially if you shop for used tires.  Since you'll be racing an odd dog. The last 10th of a second won't matter. A season or two old tires  won't matter because you wont be apples to apples like you would with a Miata.  Corvette, Mustang, BMW. Etc. 

Tom1200
Tom1200 UltraDork
1/14/22 8:40 p.m.

In reply to codrus (Forum Supporter) :

I normally run in the intermediate group as that's a better fit. 

We're all kind of looking for the Goldilocks just right; not to slow or to fast relative to other cars.

frenchyd
frenchyd UltimaDork
1/15/22 7:31 p.m.
Keith Tanner said:

You're assuming that a lower power/grip car has enough acceleration available to exhaust available traction :) You're also forgetting what happens after the corner.

With the high power/grip car, the earlier you can accelerate the more speed you'll have down the straight. If you can give up 3 mph mid-corner by taking a less-than-ideal line, but gain 5 mph by the time you get to corner exit, you benefit. So it's worth squaring off the corner somewhat in that case, you're setting yourself up to apply that traction longitudinally as soon as possible. Your total time in the corner may be longer but your time on the straight will be less.

Same thing happens to some extent on corner entry.

I'm lucky to have access to very similar cars with radically different power/grip ratios. I definitely have to adjust my lines to get the best lap times, and it's more obvious on some cars than others. In one case - a chicane exit - it's worth taking a line that goes diagonally across the track in the high power/grip because I can get on the power sooner and longer. In a car with the same suspension and tires but half the power, I take a more arcing line to maintain as much speed as possible down the short straight. My line through the chicane is almost identical because there's no way to deploy the power anyway.

Of course, it's not black and white. As noted, it's relative. And as soon as you're trying to deal with another car mid-corner, the rules change :)

Are you racing wheel to wheel or just a track day?  
    If you're racing for position lines mean almost nothing. It's your relative positions. 
 The car in front can dictate the the circuit to the car behind. You trade lap time for positioning. 

mr2peak
mr2peak Dork
1/16/22 12:06 p.m.

I think the grip levels of modern cars kill the fun. Power means nothing without grip. Low grip means cornering balance is more important, and throttle skills come in to play more often.  200TW tires are great for lap times but put you way above legal speeds for anything approaching the limits.

Keep the power, lower the grip, and use your skills and judgement to keep yourself pointed in the right direction.

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
1/16/22 1:20 p.m.

In reply to mr2peak :

Then the Frisbees come with low grip tires and people wail and gnash their teeth.  Can't ever win.

350z247
350z247 Reader
1/17/22 1:55 p.m.

In reply to Pete. (l33t FS) :

Because that's idiotic. Let's take a college track athlete and make them run in their dress shoes instead of spikes. It makes no sense to spend all this time and money building a competent car to then hobble it with garbage 500TW econo tires...

frenchyd
frenchyd UltimaDork
1/17/22 8:36 p.m.

In reply to 350z247 :

Perhaps you haven't thought things through?  
 Older stuff updated to be competitive with new stuff is nonsense.  
      More power, more traction,  and you've lost originality.  Sure it can be done if you spend enough money, but why? 

maj75 (Forum Supporter)
maj75 (Forum Supporter) Dork
1/17/22 10:57 p.m.

In reply to Tom1200 :

So you evidently haven't had to drive with your arm out the window giving 15 individual point-bys to the cars coming up fast in the mirror.  30+ cars on track, no point bys in the corners, gets old.

Tom1200
Tom1200 UltraDork
1/18/22 12:31 a.m.
maj75 (Forum Supporter) said:

In reply to Tom1200 :

So you evidently haven't had to drive with your arm out the window giving 15 individual point-bys to the cars coming up fast in the mirror.  30+ cars on track, no point bys in the corners, gets old.

How about 43 cars on a 1.8 mile track at a vintage race with a gap between the fastest and slowest cars being 20-25 seocnds. This is way busier than any track day.

 At the PCA events I instruct at I do indeed end up waving 20-25 cars by at some events.

Here is where I am at: if you can only pass on the straight then who really cares of there are 15 cars stacked behind you. You can get them all by on one straightaway. In a 30 minute session you may have to do this twice.

So what we are talking about is 2-3 minutes of the 30 minutes involve waving people by.

I have no problem with anyone not wanting to deal with having to do a bunch of  point bys. All I'm saying is I personally don't have an issue with it. As I previously mentioned you just need to have a different attitude and a plan to manage things before you go on track.

What I don't agree with are the statements people make about needing to have a car with at least 300hp to enjoy a track day......that's all I'm saying.

 

Tom1200
Tom1200 UltraDork
1/18/22 1:00 a.m.

OK so here is what happens when you take you 80whp car out in the intermediate group at your local PCA events. Fully half the field passes you, this was probably the least busy session for the day.

A couple of notes; the Hoosiers are shot, so not only is the car slow on the straights it's slow in the corners, the oversteer was fun but slow. Next please ignore the shuffle steering, I was still nursing an issue with my right shoulder.

On track video starts at minute 10.........cuz I suck at editing.

https://m.youtube.com/watch?v=QcLeGQTMyGY

Our Preferred Partners
ZfCh51DoSsXAP5uZdmwJ8eDx95efOn8p9DooK1bjCYbXy8LXoIRN1DzXzic1spw8