Mid Engine AWD

Author
Discussion

43655

Original Poster:

54 posts

158 months

Thursday 16th April 2015
quotequote all
Bit of background, designing and fabricating a mid engine 'pickup' tube chassis etc Audi 2.7tt V6

Lambo once used a mid engine with the gearbox infront of the engine, and a driveshaft running back to a diff behind (or under?) the engine.
The R34 Skyline, Sierra and the 1000hp KRB Quattro to name a few used this kind of system, the other way around mind.

Although the classic mid engine drivetrain look will be lost a bit, the weight will be much more centred (assuming there will be space between the seats for the gearbox nose and transfer case, I haven't modelled any of this up yet)

A Volvo 940 diesel gearbox supposedly matches Audi bolt patters, a transfer case wouldn't be hard to do, but i'm stumped at the centre-diff part, how the hell does that work? Adjustable bias and stuff.
Maybe an off-road diff and transfer case could be used?
The idea appeals, not only from the better PMoI (albeit at a weight penalty) but also due to the legendary Quattros being a bit inspiration, and reading about cars like the Ultima that struggle to put their 5/600hp to the ground even through 315 tyres.

These are just bored-at-work-musings at the moment, and also becuase I can't afford a Porsche G50 'box!

Looks promising though


Please discuss!

anonymous-user

53 months

Thursday 16th April 2015
quotequote all
2 letters, 3 numbers: RS200 ;-)


(or how to get a mid engined 4wd powertrain into a short / narrow chassis!)

anonymous-user

53 months

Thursday 16th April 2015
quotequote all

43655

Original Poster:

54 posts

158 months

Friday 17th April 2015
quotequote all
so they have engine and clutch in the back, driveshaft to gearbox in the front and drive side to side and rearwards.
surely the only gearbox usable for something like that would be an RS200 one?
doesn't look like something so easily adaptable from standard parts

Really impressive though, never looked at the workings of it. the Pug 206 T16 is an interesting one too

Would it be unnecessary weight and complexity for a road car though?

stevieturbo

17,229 posts

246 months

Friday 17th April 2015
quotequote all
43655 said:
Bit of background, designing and fabricating a mid engine 'pickup' tube chassis etc Audi 2.7tt V6

Lambo once used a mid engine with the gearbox infront of the engine, and a driveshaft running back to a diff behind (or under?) the engine.
The R34 Skyline, Sierra and the 1000hp KRB Quattro to name a few used this kind of system, the other way around mind.

Although the classic mid engine drivetrain look will be lost a bit, the weight will be much more centred (assuming there will be space between the seats for the gearbox nose and transfer case, I haven't modelled any of this up yet)

A Volvo 940 diesel gearbox supposedly matches Audi bolt patters, a transfer case wouldn't be hard to do, but i'm stumped at the centre-diff part, how the hell does that work? Adjustable bias and stuff.
Maybe an off-road diff and transfer case could be used?
The idea appeals, not only from the better PMoI (albeit at a weight penalty) but also due to the legendary Quattros being a bit inspiration, and reading about cars like the Ultima that struggle to put their 5/600hp to the ground even through 315 tyres.

These are just bored-at-work-musings at the moment, and also becuase I can't afford a Porsche G50 'box!

Looks promising though


Please discuss!
if you cant afford to build a lot of custom parts ( ie that will cost far far in excess of a G50 ) then maybe the 4wd aspect is a bit ambitious ?

I'd be surprised if an Ultima with mid engine/rear box would really struggle with traction that badly at only 500hp.
Even my own heavy car with front engine, mid box and rear drive 235 tyres when it's as low as 500hp gets pretty good traction.

Nissan GTR uses front engine, rear trans and tansfer and then a shaft running rear to front for the front diff/drive.

A quick google brings uop this old thread, which seems to show a similar option ( albeit much simpler from a post by Fat Panda, Sadev SL90-20 trans )

Cant imagine it being cheap either.
But it offers you fitment for mid engine, rear trans and with a transfer box on the back to give you a shaft to run rear to front.

http://www.pistonheads.com/gassing/topic.asp?t=745...

R32, R33, R34 etc you refer to are not like that.

They are front engine, mid mount trans bolted direct to the engine with a transfer box on the rear of the trans and then a shaft running both rearwards and forwards for each axle drive.

At the cheaper end of the scale, if you could bolt say a 4wd Audi or maybe Subaru 6 speed and adapt a conventional type transfer box to the rear of them, that could offer you the transaxle style box, and also a forward travelling shaft for the front drive.



Edited by stevieturbo on Friday 17th April 13:13

Luther Blisset

391 posts

131 months

Friday 17th April 2015
quotequote all
what about something like this? obviously you'd need to remove the final drive unless you actually want a 40mph top speed

http://www.offroadfabnet.com/forums/showthread.php...

stevieturbo

17,229 posts

246 months

Friday 17th April 2015
quotequote all
On a similar vein to the above, and as you see on the likes of Scrapheap Challenge etc.

If you can get a suitable say V6 engine from a FWD vehicle, transverse mount, then install it longitudinally in the back, that could then provide fore/aft drive and cost very little.

Not sure what you'd do for front/rear diffs though

chuntington101

5,733 posts

235 months

Saturday 18th April 2015
quotequote all
You could also look at using a Audi 4wd gearbox. It would require a pretty long driveshaft of the rear of the box to the front axel but that's how lambo/Audi have been doing it for some time now.