Learn me "small" liter, high HP engines.

Just for the record, I like this idea. Please stay away from snowmobiles and their CVTs though. I frequented a dragstrip in my youth, and there was a clever guy who built a 5/8ish scale dragster with that powertrain, trying to go fast for cheap. It ran mid tens and wanted to make me stab my ears every time it ran. Just the constant drone of a terrible exhaust note for nearly eleven seconds.

waaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Every time he came to the line, I could see many people turning and walking away.

In reply to tuna55 :

Oh look a fire, lets poor gasoline on it!

F-mod / Formula 500 was voted most annoying class at Solo Nationals...................why? The real reason is  the car costs less than people spent on shocks/dampers is 3 seconds faster. That low flying ultra-lite exhaust note is a constant reminder. 

OK on a serious note; Two strokes are light and make 200hp per liter or more. They are also extremely reliable; they typically only have a failure is if you've gotten the jetting horribly wrong. Now that snowmobile engines are fuel injected it makes them even more attractive. 

The guy who runs Balto(snowmobile miata) said he gets in the car and floors it for 2 hours at a time. Same RPM for 2 hours. Same exhaust note for 2 hours. Wheeee

In reply to buzzboy :

I refer to my F500 as the weed whacker; I quickly got over the constant exhaust note because the car is fast.

buzzboy said:

The guy who runs Balto(snowmobile miata) said he gets in the car and floors it for 2 hours at a time. Same RPM for 2 hours. Same exhaust note for 2 hours. Wheeee

A Top fuel dragster is basically on a CVT the way they are tuned. It's okay because a Top Fuel engine sounds like the world is ending in a flurry of glorious horsepower. A snowmobile sounds like my grandmother snoring.

tuna55 said:

buzzboy said:

The guy who runs Balto(snowmobile miata) said he gets in the car and floors it for 2 hours at a time. Same RPM for 2 hours. Same exhaust note for 2 hours. Wheeee

A Top fuel dragster is basically on a CVT the way they are tuned. It's okay because a Top Fuel engine sounds like the world is ending in a flurry of glorious horsepower. A snowmobile sounds like my grandmother snoring.

Yeah, the effect is the same, but it's a progressive clutch vs a band on cones with opposite facing slopes. 

 

A Top fuel dragster is basically on a CVT the way they are tuned. It's okay because a Top Fuel engine sounds like the world is ending in a flurry of glorious horsepower. 

This is the quote of the year.

The 1.0 l Ecobost 3 banger turbo that Ford had as an option in the Fiesta and (I think) the Focus in the states is very light and can be tuned to make quite a bit of power.  Not as fun as adapting stuff but could be an easy way to get a zany and tractable power to weight ratio.  

Formula 1 engines make as much as 1350 hp ( 4 cylinder BMW ) and weight as little as 95 KG. ( Ferrari V10 ) 

In reply to Shaun :

Apparently they are difficult to make work in other chassis.  Unless that has changed.  I love them and want one.  I've considered just getting rid of all the DI stuff and running basic normal FI in a custom manifold.

Forget a Jet Ski motor, adapting a cooling system isn't worth the squeeze.  Liquid cooled, fuel injected snowmobile if you must.

In reply to maj75 (Forum Supporter) :

Why is adapting a cooling system an issue with them?  I know the water pump is usually off the jet drive, but you can usually find an electric pump for a decent price.

I'm also finding that many of the snowmobile/jet ski engines aren't that power-dense.  Many of the 600cc jet ski engines I find are in the 50-60 hp range.  Not really a big power-to-weight ratio savings.

Quad 4 isn't a bad choice.  2.4L and really easy to make 250 hp for 300 lbs.... which seems like a good trade-off for your 200-lb 600cc engine until you realize that your 200 lbs includes the transmission.

Take a look into Hyabusa 1300ccs with turbos.  Not exactly light and probably not budget friendly, but maybe worth a shot.

My understanding is a Turbo Hayabusa has been done on a challenge budget before...

My 2 cylinder 2 stroke 494cc engine from the 90s that I can lift by hand (with transmission) without breaking a sweat puts out over 100hp...  The car it's in, without driver weighs 650lbs.  Go ahead and hate the noise, I'll be at the finish line seconds ahead of you waiting having spent a fraction of the money. I've learned to love the car.

Now, granted, piped 2 smoke can get to some people. Here is a 4cyl 4 stroke with turbo putting out 280hp.

(I want to put that engine in an amod so bad) 

Can you get over the lack of shifting? It's faster missing that you know, no shift lag, no time wasted waiting to be on the peak powerband, no worrying about the gearing being right to pull out of a turn or else you aren't on the cam/pipe...  

Besides, electric vehicles don't shift either. 

A lightweight and fast car with seamless power delivery for cheap... Only drawback is it sounds like a hot saw competition.  Why is it a hard sell?

IIRC, the snowmobile miata still makes around the same 92-94 whp as the 1.6 lump did...but the car is like 1700 lbs.

The outboard idea is intriguing.  Non-running outboards are stupid cheap. 

An interesting cross-section of small automotive engine and snowmobile CVT exists in the Arctic Cat T660 turbo. It's a Suzuki K6a 660cc turbo kei car engine, with a crank adapter to mate the CVT primary clutch. I actually found the adapter itself on ebay, the crank bolt pattern seems to also match other small Suzuki engines like the Geo Metro G10 and G13-G16 4 cylinders. 

For even more absurd power potential in an absolutely tiny package, there's the Arctic Cat Z1 Turbo four stroke. Tuners advertise 300+ hp out of the 1100cc engine.

Apexcarver said:

https://www.youtube.com/embed/LQNafmhaE2w?rel=0

 

Can you get over the lack of shifting? It's faster missing that you know, no shift lag, no time wasted waiting to be on the peak powerband, no worrying about the gearing being right to pull out of a turn or else you aren't on the cam/pipe...

One of the Nelsons (I am HORRIBLE with names, Calvin I think?) was talking in the stands at the drags about how a well setup stall converter essentially acts like a CVT and the engine stays in the same powerband the entire time, dropping only a few hundred RPM when shifting.

If its good enough for the Nelsons...

In reply to Mr_Asa :

I've often wondered if for a light enough car, you could just run a big V8 with a torque converter and no transmission.  Gear it so you use the torque converter for 0-30 MPH then run the rest of the engine RPM until 65-70.  May need to have a second gear set (or much larger diam wheels) for drags to run 105-110 trap speeds.  I'm just not sure what the fluid requirements for a Converter are if you could realistically figure it out and save 75 lbs of transmission.

In reply to Apexcarver :

I'm sure I've mentioned it before but I think I stopped caring about shifting on lap 2 the first time I took my F500 around a road course. 

For autocross the CVT is a huge advantage as you well know and as you pointed once you see your time you quickly forget about not having a manual gear box.

It's not something most people know, but you can actually build a 2-stroke V6 out of the front half of a Jaguar V12.  I've done the machine work before with a dingleberry hone on a brace and bit hand drill and a Swiss army knife.  The end result went in my XJ-S for an endurance race.  It was a 24 hour grudge match at Elkhart Lake, just me in the XJ-S versus Jackie Stewart in a Lotus 77.  If I remember correctly, I won by six or seven laps and he immediately retired from racing to become an Olympic skeet shooter.  I have pictures, but my scanner is broken.

In reply to Mr_Asa :

And, for a given power and weight, what's more efficient? Working the fluid through a converter or the belt and moving sheaves? I'm pretty sure the sheaves waste a lot less power than what goes into frothing and heating the trans fluid. Also, the weight part of the equation...

If you go over to my F500 thread, I have a link that puts in car footage side by side of my F500 vs Gimpy's CP car. That comparison will show why I giggle every time I run my f500... IT SCOOTS.  I also have footage side by side with a shifter kart and I can hang until the braking zone for the first real turn, but with a whole lot less work from the driver.

totallynotmguar said:

It's not something most people know, but you can actually build a 2-stroke V6 out of the front half of a Jaguar V12.  I've done the machine work before with a dingleberry hone on a brace and bit hand drill and a Swiss army knife.  The end result went in my XJ-S for an endurance race.  It was a 24 hour grudge match at Elkhart Lake, just me in the XJ-S versus Jackie Stewart in a Lotus 77.  If I remember correctly, I won by six or seven laps and he immediately retired from racing to become an Olympic skeet shooter.  I have pictures, but my scanner is broken.

LOL.

Apexcarver said:

In reply to Mr_Asa :

And, for a given power and weight, what's more efficient? Working the fluid through a converter or the belt and moving sheaves? I'm pretty sure the sheaves waste a lot less power than what goes into frothing and heating the trans fluid. Also, the weight part of the equation...

 

If you go over to my F500 thread, I have a link that puts in car footage side by side of my F500 vs Gimpy's CP car. That comparison will show why I giggle every time I run my f500... IT SCOOTS.  I also have footage side by side with a shifter kart and I can hang until the braking zone for the first real turn, but with a whole lot less work from the driver.

Link please.............I really want to see that video.

psteav (Forum Supporter) said:

IIRC, the snowmobile miata still makes around the same 92-94 whp as the 1.6 lump did...but the car is like 1700 lbs.

The outboard idea is intriguing.  Non-running outboards are stupid cheap. 

I have wanted this for years, but I can't figure out a decent way to get them to run horizontally.  I suppose you could lay them on their side and build a thing to rotate the carbs 90 degrees but I would think you might get abnormal cylinder wear.

You also have to do some internal mods (depending on the power head) to prevent the cooling water from joining with the exhaust