Cheap, Light, Powerful, RWD. Possible?

Satrun LLO + T5??? This forum never ceases to amaze me . . .

If you want light weight might I suggest getting rid of the overhead cams, heck eliminate the valves and one of the cylinders for that matter.

My old Polaris XLT 580cc made around 130 hp with PSI pipes. and probably weighed 100 lbs, maybe. Oh and the power band was sweeet. Of course you'll probably want some gears out of an old mini pickup 4.75 to 1 or 5.something to 1.

In reply to bigben:

I was just thinking that. 2 stroke snowmobile engines are very powerful and very very very light. Many ultra light airplane guys use them.

The newer ones are running factory turbo set up 4 strokes at ~180hp.

What about a 2ZZ-GE, 250ish lbs, high 100's hp, can be had in a FWD or MR platform? Of course I would always suggest a 13B and a good rebuild kit first though

Given your power goals, I really doubt you are going to beat the Suzuki G13 for weight unless you consider a bike engine. My primary experience is with the Toyota 4A-GE...which are light enough that picking it up by hand is an option, and my experience with the G13 was that it was noticeably lighter than all those 4A-G's I've hefted around over the years!

I wouldn't recommend a 4A-GE as it isn't cheap to modify, and RWD transmissions are getting tougher to source. If you are going for something light, RWD, with scarce transmissions and a bit marginal in regards to your power goals, why not stick with the lighter Suzuki?

On a semi-related note, I've yet to see a longitudinal RWD 4A-GE swapped for something production-based that both increases power and saves weight. Sure, you can get more power by going rotary, F20C, or SR20, but they all end up making the car heavier once swapped.

I vote motorcycle engine. I have done a ton of research on this over the years and for your stated goals, these are impossible to beat. There are tons of options that will be readily (relatively) available. Get at least 1l engines as the lack of torque on the 600cc engines is a real issue in a car.

Gsxr 1100 for $850 that wiki says is 155hp. There is likely a few items you can sell along with it. Motor combo can't weight much more than 200 lbs.

If you are interested in chatting about this let me know

Would it be difficult to push 125 na hp out of a 16v G16?

how much does a na sr20 weigh?

In reply to yupididit:

I haven't weighed one myself, and I've heard some crazy claims over the years, so I am happy to stand corrected if someone steps in with confirmed specifics. The most consistent numbers I hear are about 470lbs for the RWD turbo, fully dressed with transmission, manifolds, turbo, the whole enchilada. How much lighter would a rear-drive SR20DE be than the SR20DET? I dunno, but I'm gonna guess it probably isn't in the sub-300 pound range of some of the other options discussed.

Bike engine is a good choice if its intended and designed around a single focus and street use isn't it.

Easiest is to front mount the engine and use a ready made driveshaft adapter to a diff of your choosing,steep enough ratio to launch decently means your not going to go much more than 100mph.I used a miata rear in one of my builds with the 4.3,it was ok for autox and small rd course fun.

Remember that bike engines blow pretty easily in a car unless you take steps to control the oil in the turns,R1 is the most reliable in this regard only needing a baffle plate.I used R1's in both my builds with no problems,stock clutch except for a double spring.

Transverse with chain drive will take up a fair bit of time fab that up and make the diff hold oil and have some form of chain tensioning.

I've done it both ways,autox car used an easy to source driveshaft adapter and I actually used a miata half shaft for a driveshaft as they were close together and had an angle to deal with that u-joints wouldn't have been happy with.

Ice racer was mid transverse mounted so I could jackshaft to hold a dual sprocket to go fore and aft for awd drive using diffs fabricated from the original bits from geo transmissions....a toilet plunger held the cv grease I filled the diffs with just fine.2 seasons of racing and no driveline failures.

The ice car;

https://youtu.be/_AbPkpyLRW8

The autox'r

https://youtu.be/k4rJ567ded0

My thoughts are if your able to get the weight down under 1500lbs(1000lbs would be way way better)than bike power becomes feasible.If you pick an early R1 with carbs you can boost it with very easy mods to the induction side,far cheaper than going to a standalone computer to run it.

I boosted my 4ag AE86 thru R1 carbs and they worked great,search for turbo-bikes.com I think it is for info.

If you intend to street drive the project after the challenge go car engine as it'll be much beter suited.

Btw my R1 weighed 145lbs complete with oil,even without a transmission its going to tough to find a car engine that weighs that.

How are your fabrication skills?

Buy a wrecked FWD vehicle with cable shifted transmission. Build a chassis with your welding talent, swap gear from wrecked vehicle for a mid-rear power, lightweight beast. There was a project like this a few years ago in GRM magazine. Guy built an Ariel Atom knockoff with Honda drivetrain.

Knurled wrote: Besides, it's a perfectly cromulent excuse to run rearend gears that start with a 5.

You have embiggened me.

I like the LL0 idea. The LL0 had a pretty square output of 124hp/122ftlbs which made it quite torquey for a sub 2 litre N/A. I've seen it done RWD with webbers once before, I wish I could find the thread... It's been like 14 years since I've been in the saturn community.

I do know that you can get close to 150 out of a saturn motor using only stock parts if you mix and match components from different years.