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Lof8
Lof8 GRM+ Memberand Dork
6/27/17 8:26 a.m.
irish44j wrote: RWD guys have more fun though ;)

thats the important takeaway here :)

Knurled
Knurled GRM+ Memberand MegaDork
6/27/17 12:24 p.m.
Jaynen wrote:
Knurled wrote: In reply to rslifkin: More power has always helped my RWD car. My AWD car had maybe 80hp. Its twin is maybe going to have 400hp, I hope that is enough to allow it to accelerate hard enough to be thrown into tight corners so it can turn easily. If not, I can find a couple hundred more HP with a head swap. I think heads would explode if I showed up to Nationals with 600hp.
You feel like power makes a big difference for RWD? There was a straight 6 E30 there at the practice day and he just seemed to be drifting the whole time but not getting a lot of thrust Edit meant RWD

I can corner better when I can decelerate into the corner. Can't power into/through a corner with RWD, have to wait until you're pointed straight.

Note that I don't drive a Miata, I drive something with a solid axle so therefore I can actually put power down.

Knurled
Knurled GRM+ Memberand MegaDork
6/27/17 12:30 p.m.
rslifkin wrote: I'm not sure just how much power is really usable on a typical course. With a locked center diff, reasonably worn but still somewhat useful LSD rear and open front and 350-ish hp at the crank, I've never found a point on a course (even at 40+ mph) where putting my foot to the floor didn't lead to massive and immediate wheelspin (with ~4500 lbs of Jeep and driver pressing down on the tires).

What KIND of tires? Truck tires with hard rubber compound (no grip) and solid tread blocks (no grip), or rally tires?

The Indy Sport tires shouldn't have as much grip as they do because they have solid tread blocks, but their rubber compound is somewhere between pencil eraser and Silly Putty, so they gots the grip. If they put grip sipes in the tread blocks then they'd be even better but they'd also probably only last half as long... and their life already seems to be short enough that you would need to replace them mid-season. (Which is most of why I don't have any )

rslifkin
rslifkin Dork
6/27/17 2:14 p.m.

In reply to Knurled:

For tires, I've had that experience both on soft-ish, lightly grooved mud tires (225 width) as well as snows (235 width), and one set of runs on a set of General Grabber UHPs (255 width). This is on a variety of different course surfaces too. In any case, I could put down a decent amount of power, but never WOT without wheelspin. Combos used were the M/Ts on both wet grass / dirt as well as packed dirt / gravel, the snows on both of the above and the UHPs on damp grass / dirt.

At the site that's mostly packed dirt / gravel, once any snow is gone, tire choice doesn't seem to make a huge difference in grip during the colder months. I've seen 2 very good drivers in almost identical cars turn in very close times with one on either studded snows or gravels and the other on all seasons. I had slightly more grip there with my snows than with the M/Ts, but it wasn't a huge difference.

There's one site I haven't gotten to run at where the dirt has dirt track levels of grip supposedly, so it's not uncommon to see people run summers there with good results. In that case, I might be able to use all the power.

Jaynen
Jaynen SuperDork
6/27/17 3:20 p.m.

I would not have put together that a stick axle was better in the dirt for RWD but I guess it makes sense for the same reasons guys want straight front axles for 4x4 off roading?

Whats an Indy sport tire?

moxnix
moxnix HalfDork
6/27/17 3:23 p.m.
Jaynen wrote: Whats an Indy sport tire?

http://rally.build/category/products/rally-tires/

Knurled
Knurled GRM+ Memberand MegaDork
6/27/17 4:38 p.m.

FWIW, I found a lot more bite going from 205 and 215 width rally tires to 185s. Dirt is different than asphalt like that... I get the best front cornering bite when the inside front is off the ground You want to drive maximum pounds of force per square inch of tread block on the ground for maximum grip, at least on dirt/clay.

irish44j
irish44j UltimaDork
6/27/17 5:42 p.m.
Jaynen wrote: I would not have put together that a stick axle was better in the dirt for RWD but I guess it makes sense for the same reasons guys want straight front axles for 4x4 off roading? Whats an Indy sport tire?

That's Pete's opinion on the matter, at least for his driving style. Pete drives a totally different style than I do, for instance. My style would not be great with a solid axle, and his would probably be less than great with an IRS RWD car. Other than Pete and a couple others, there aren't a whole lot of guys doing well in rallycross with solid rear axles these days. But then again, most of those cars are heavy land-yachts. YMMV, as always. Don't overthink it. If you can drive well, you can be fast at rallycross in a variety of different types of cars/suspension/power levels as long as you set them up correctly.

I agree with Pete on the tires though. narrower tires definitely grip better on most dirt/clay surfaces (wider tires seem to do better on straight gravel). I switch between 175s and 185s (which are really more like 165s and 195s in actual tread width in the Dmacks) and there is a substantial difference in handling and grip.

Knurled
Knurled GRM+ Memberand MegaDork
6/27/17 6:56 p.m.

The kicker for me was at the event where you came up to play with us in Ohio and I was running on 185/65-15 snow tires, and debeaded for the first time in my life (driver's rear), so I switched the rear tires to my backup 235/45-17 snow tires... and promptly spun in like the third corner because there was far less grip. And the 235's were relatively chunky tread pattern Mastercrafts while the 185s were the slick-like Altimax Arctics.

Some people can be told and some of us just need to whizz on the electric fence

Jaynen
Jaynen SuperDork
6/27/17 8:01 p.m.

Yup, my montero was shorn in tall and skinny goodyears for that reason. Its something the overlanding crowd knows but the mall cruiser crowd doesn't

irish44j
irish44j UltimaDork
6/27/17 8:05 p.m.
Knurled wrote: The kicker for me was at the event where you came up to play with us in Ohio and I was running on 185/65-15 snow tires, and debeaded for the first time in my life (driver's rear), so I switched the rear tires to my backup 235/45-17 snow tires... and promptly spun in like the third corner because there was far less grip. And the 235's were relatively chunky tread pattern Mastercrafts while the 185s were the slick-like Altimax Arctics. Some people can be told and some of us just need to whizz on the electric fence

hah, yeah I remember that. Of course that was after I had a complete spin on the first run (on fairly worn 185 gravel tires...thanks wet grass and being 2nd on course first thing.....)

Curious - I noticed them in the supps for this event, but do other national/divisional evens allow a re-run for a debead? I don't think you got one at that event, but not sure.

Knurled
Knurled GRM+ Memberand MegaDork
6/27/17 9:00 p.m.

At the time, a debead was a DNF.

As of last year (maybe 2015), National rules allow a rerun if you debead. Which I think, personally, is kind of reckless, since it encourages people to drive in such a way that they risk debeading...

Whether I like it or not is immaterial, that's the sandbox we're playing in, take advantage of what you can.

irish44j
irish44j UltimaDork
6/27/17 9:20 p.m.

I kind of thought the same thing...like, ok it's muddy so I'll just air down to 10psi and if I debead....well, I get another shot at it. It encourages serious low pressures since there's no penalty. I will certainly keep that in mind at the East Coasts (and keep a spare wheel/tire at my grid spot lol).

I'm all for "if you debead, just keep going, this is rallycross not autocross..." But even at local events where you don't get a re-run, they'll red-flag you for debead if they notice (though three e30s debeaded rally tires our last event, which is VERY rare at this venue, and nobody noticed so they finished their runs)

Knurled
Knurled GRM+ Memberand MegaDork
6/27/17 9:24 p.m.

If nobody red flags a debead, that is seriously shame on the corner workers.

I'll admit to not stopping after I debeaded in 2013 or whatever year that was that OVR held the Eastern or Great Lakes or whatever championship. I thought something in the suspension broke, so i figured, eh, we're still mobile, keep going and worry about it after the run is over. Then I spun.

OTOH I was at an event where a Golf almost rolled, and did turn a control arm into a V shape, when it debeaded and the rim lip made like a shovel. (Not ZB's Golf) So stopping cars with a debead makes a lot of sense from a safety point of view.

irish44j
irish44j UltimaDork
6/27/17 9:37 p.m.

well, light cars on gravel tires, with debead on front wheel. Not always obvious, especailly with the dust we had last event. Oddly, the same e30 did it twice with two different drivers, on Dmacks runnign typical pressures. And these dudes had previously NEVER debeaded in 8 years of rallycrossing lol...

irish44j
irish44j UltimaDork
6/27/17 9:59 p.m.
Knurled wrote: If nobody red flags a debead, that is seriously shame on the corner workers. I'll admit to not stopping after I debeaded in 2013 or whatever year that was that OVR held the Eastern or Great Lakes or whatever championship. I thought something in the suspension broke, so i figured, eh, we're still mobile, keep going and worry about it after the run is over. Then I spun. OTOH I was at an event where a Golf almost rolled, and did turn a control arm into a V shape, when it debeaded and the rim lip made like a shovel. (Not ZB's Golf) So stopping cars with a debead makes a lot of sense from a safety point of view.

Yeah, I remember watching you debead at Great Lakes (it was 2014) and remember thinking about how before we started you were talking about the advantages of snow tires vs. my worn out gravels lol...

I agree and disagree about debeads. One of the things our rallycross director says before every event is this: We are not responsible for you, your car, or your driving. YOU are responsible for you, your car, and your driving

And that's totally true. If you debead, you know it immediately (or think you broke suspension), so it's up to the driver to let off. You can finish a run on a debead albeit with a slower time. If you decide to say "berkeley it" and go balls-out with a debead (or a broken suspension piece), and you bend the control arm into a V or do something else worse to the car, that's a risk you take I guess. Stage guys run miles on debeads, sometimes two of them (and/or broken suspension pieces) at much higher speeds, and contrary to what you think there are plenty of hairpin turns and stuff where such things could roll the car or send it into the trees. So they lift off and go slower and finish. Not sure why rallycrossers can't do the same.

I personally don't think you should get a red flag, nor that you should get a rerun for a debead. You will say "it's a safety issue." Well sure. If the driver recklessly pushes with a debead it is indeed a safety issue. But if a driver goes too fast on four good tires and flies off into the woods, that's a safety issue too. It's on the driver to not wreck his car, whether from going too fast, driving out of control, or driving too hard with a debead or blown shock or whatever.

My 2 cents, and I'm sure the counter-argument is about SCCA insurance coverage and liability. That may be the case, IDK......

I personally only think a red flag should come out if a car is stopped on course, or a small child is wandering on the course. If a car can proceed on the run (whether slow or fast) the should be permitted to. But I don't make the rules ;)

Jaynen
Jaynen SuperDork
6/27/17 10:22 p.m.

Pretty Volvo that would be a fwd one I'm guessing

ProDarwin
ProDarwin PowerDork
6/28/17 7:57 a.m.

On the subject of de-beads and red-flags. IMO it is a safety issue and a potential insurance issue for the club. Rallycross doesn't require a cage so rollovers aren't exactly 'safe'. Additionally they can berkeley up the venue the club is using. Most regions don't want to spend a day picking glass out of the course after a rollover.

At big events, maybe. But at small events, I think the avg. driver experience is way too low. Its kind of like telling someone with a tall car at an autocross to just "drive around" the issue so they don't roll the car. The SCCA has a policy on this and it includes just banning the vehicles to avoid the problem (although IMO they need to be more stringent on this requirement).

irish44j wrote:
Jaynen wrote: I would not have put together that a stick axle was better in the dirt for RWD but I guess it makes sense for the same reasons guys want straight front axles for 4x4 off roading?
That's Pete's opinion on the matter

Indeed.

Stick axles have low ground clearance in the center compared with a well done IRS setup. Increasing ride height on an IRS will improve clearance, whereas with a beam axle you have to increase the tire diameter. Its annoying on a FWD car, but tolerable, as the axle is a lot smaller. On a RWD car you get a big pumpkin hanging down in the center.

Also, bump travel seems compromised. See knurled's comment in the other thread regarding Sentra suspension travel. There is a pretty hard limit on travel as the beam/axle can only move up so high until it hits the body. In many cars there is probably reasonable space there, but an econobox where trunk space is a premium, its pretty tight. Only a few inches between the beam and the body, minus some room for spring seat, bump stop, etc. doesn't leave much space for real travel.

A solid axle can work very well if setup right, but I don't see why any of them would work better than an IRS setup.

rslifkin
rslifkin Dork
6/28/17 10:43 a.m.

Tire width seems to depend on the surface and tread pattern. On something solid that packs down well, wider will often give more grip. Same with packed snow. But if you're in fresh, loose snow or loose dirt (especially with solid dirt under it), narrower tires will cut through and get down to something grippy much better than wide ones will.

Weight of the car also affects what counts as wide or skinny. A 225 on a 2500 lb car is a lot "wider" than a 225 on a 4000 lb car.

For the solid axle thing, they don't necessarily work better, although the lack of camber loss with body roll can be good if you're running marshmallow springs. And solid axles tend to be easier to set up and tweak, which can be an advantage. Well sorted independent suspension will typically be better on terrain like a rallycross course though.

With that said, I've never really felt like my stick axles have really been what's holding me back (even up front). Then again, I do have a "weird" setup for rallycross. Compared to a lot of cars that are on stock springs with no sway bars, etc. I have some of the stiffest springs of anyone in my local area for rallycross. A few times I've seen others run stiff setups though. It doesn't really seem to hurt much. Makes the car more responsive, so you have to be a little more careful not to over-drive your grip, but total grip doesn't suffer much.

Knurled
Knurled GRM+ Memberand MegaDork
6/28/17 12:32 p.m.
ProDarwin wrote: On the subject of de-beads and red-flags. IMO it is a safety issue and a potential insurance issue for the club.

Oh it is 100% an insurance issue as well as a safety issue. If you lose sanction because insurance won't cover you, you can't run no matter how safe you want to be.

Stick axles have low ground clearance in the center compared with a well done IRS setup.

Should be immaterial, at rallycross. Courses must be designed such that they are navigable by street stock vehicles without damaging them.

The low point of my car isn't the rearend, anyway - it's the front crossmember. It used to be the skidplate but it's kind of bashed up now. I hit "something" on the highway one night that made the whole car jump up in the air.

A solid axle can work very well if setup right, but I don't see why any of them would work *better* than an IRS setup.

Antisquat. You can't get enough of it with IRS.

I like having a car where, when you hit the accelerator, the back end plants and you accelerate. I don't have power on oversteer unless I was already spinning out. If I'm sliding around a corner, I accelerate and the car straightens out.

The steering is next to useless, but it's not a finesse car, it's more of a bludgeon. Long tight corners tend to be "square" - enter, accelerate, lift to turn, accelerate again. No silly crab-walk driving

ojannen
ojannen GRM+ Memberand New Reader
6/29/17 4:05 p.m.

Are there any hotels near the venue? The closest ones I see are in Fredericksburg.

moxnix
moxnix HalfDork
6/29/17 4:08 p.m.
ojannen wrote: Are there any hotels near the venue? The closest ones I see are in Fredericksburg.

Not sure how close the ones in Fredericksburg are but the suggested close hotels from the owners of the rally farm are.

HOTELS:
Hampton Inn Warrenton - 501 Blackwell Rd, Warrenton, VA - (540) 349-4200 (26 minutes)
Holiday Inn Express Warrenton - 410 Holiday Ct, Warrenton, VA - (540) 341-3461 (26 minutes)
Baymont Inn Warrenton - 7379 Comfort Inn Dr, Warrenton, VA - (540) 349-8900 (26 minutes)
Poplar Springs Inn & Spa - 5025 Casanova Rd, Warrenton, VA - (540) 788-4600 (17 minutes)

Knurled
Knurled GRM+ Memberand MegaDork
6/29/17 4:45 p.m.

Hooray for camping!

JtspellS
JtspellS SuperDork
6/29/17 5:49 p.m.

Im trying to make it!

ojannen
ojannen GRM+ Memberand New Reader
6/29/17 9:19 p.m.
Knurled wrote: Hooray for camping!

I prefer to poop with air conditioning.

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