Which powertrain Layout is the Best?

[NewyorkKopter]

Hey, i was wondering which powertrain layout is the best for a high power mid-engined supercar

-Lamborghini's Layout with the gear box first, then the engine,and the rear axle

-The 1980 Group C racer Layout, with the engine first, then gear box w/rear axle

[Black Lotus]

The "1980 Group C racer Layout".
There, I said it!

[TheSilentChamber]

It probably depends more on the car and where it will fit and budget compaired to which is "better".

[curtis73]

There is no best answer. Mid engine layouts are fantastic for balance and handling, but do nothing for interior space and noise. What is the intended purpose of the car?

[NewyorkKopter]

the purpose of the car is for track racing, and some road use. I need to know which set up is better overall. Like performance wise, reliability, etc

[Black Lotus]

Originally Posted by NewyorkKopter

the purpose of the car is for track racing, and some road use. I need to know which set up is better overall. Like performance wise, reliability, etc

There is , in fact a best answer- it's mid-engined. If you are building a "super-car", the car's mechanical layout and weight distribution must come first for the best vehicle dynamics. The driver's compartment may be cramped, and there may be no storage space compared to a Camry, but who cares? (Quote: If it's not hard to get into, it's not a real sports car!)
If you are going to build a mid engined car, unless you are filthy rich, you will have some serious transaxle price and availability contraints. The transaxle may well be the single most expensive component of the car. A reasonably strong transaxle for a longitundinal engine layout will cost you many thousands of dollars used. What you would probably end up with- is something of the *engine---clutch-differential-gears* sort of layout. Or to put it in another way- a ZF out of a Pantera, a Porsche gearbox, Renault UN-1, Audi, etc. The race version replacements for some of these boxes is about $25,000. A race gearbox, while strong and fast shifting is NOT suitable for the street.
Just my 2 bits.

[NewyorkKopter]

yea thats tru i dont really care about the space in the cabin, but never mind that. which layout is better for a mid-engined supercar? then again why isnt a race gearbox suitable for the street?

[Moppie]

Originally Posted by NewyorkKopter

which layout is better for a mid-engined supercar?

You've been given the answer, but it appears your haivng some trouble understanding it.

There is no single lay out that is better than any other.


Engines are mid mounted for for two reasons:
1)Weight distrabution. to improve handling

2)Reduce the number of driveline components, the more parts you have in the driveline the more power you lose turning them, and the more it weighs.
By attaching the enigne to the gearbox, and incorperating the differential in the gearbox you elminate the need for a long heavy driveshaft and provide a more direct, efficant and lighter drive to the wheels (front engine, front wheel drive is popular for the same reason).


How you mid mount the engine however really dosn't matter.
And the list of ways of doing it is enormous:
Engine, G/box, Axle
Engine, Axle, Gearbox are the two most common and provide the simplest most direct drive from the engine to the wheels.

Axle, Gearbox, Engine Axle, as Used by Lamborgihini on the Diable etc, is the simplest method of mid mounting an engine and having AWD.
It means all of the driveline parts are kept in a nice straight line, but the nessacary drive shafts are kept as short as possible.
Unforunatly there is a drive shaft that runs through the engines sump where the rear differential is also located. Its a more complex design to enginer and manufactor.

Axle, Engine, Axle, Gearbox
Axle, Engine, Gearbox, Axle again provides AWD, but this time the rear differential can be housed in the gearbox, however a long drive shaft to drive the front wheels must be run either down the side of the engine and gearbox, or through the engines sump.
A long off center driveshaft create problems with chassis design and power delivery at the front from an off centre differential.


That just covers the basic inline lay outs, its also possible to place the gear box under the enigne, or even mount the whole lot transversly (like the MR2, Lotus Elise etc) then run the gear box inline with the engine, or underneath it etc etc etc etc etc



Which layout is best then depends entirly on the design of the car.
Is its pure Group C race for? Does it have an enourmous engine coupled to a complex AWD set up, or does it used a small light weight enigne driving only the rear wheels?
Is it a big car with lots of space in the chassis? Or is it a small light weight with a short wheel base?


There is no single lay out which is clearly superior, it depends entirly on what the car needs it to do.

[Reed]

i think you said something in another post about using an american engine. if you want to do this your best bet for power, fit, balance and ease of installation would be a FWD cadillac V8 from the 80s or 90s that has the attached transaxle.

[NewyorkKopter]

oo see now I got it. So yea I'm gonna stick with the Engine, clutch, then gearbox layout. The car itself is definetly not going to have AWD, its going to be a Diablo sized lightweight driving the rear wheels only. For the engine I'm thinking a Northstar V8 or something thats light with a 6 speed Porsche gearbox. lol thanks for clearing that up

[Moppie]

Originally Posted by NewyorkKopter

Diablo sized lightweight

Right...........

[Reed]

if you want an american v8 you would have soooo much better luck using a caddie fwd v8 and just stick the whole thing in the back. hell i think a northstar is the caddie v8 im talking about. people put them in fieros all the time.

[NewyorkKopter]

nice u know any Caddys that i can get the drivetrain from?

[Black Lotus]

Originally Posted by NewyorkKopter

nice u know any Caddys that i can get the drivetrain from?

The "Supercar" dream is slip, slip, slipping away, I fear.
Tsk, tsk.

[TheSilentChamber]

I dont think it was ever much of a reality personally.