Yet another Transaxle question

MadMaxx · 03-24-04, 03:49 PM

This doesn't relate so much to a GT40 build directly, yet an overall car-building question.

With all things being equal, what options are there for a mid-engine, V8 powered vehicle (not to exceed 450hp) and a *6spd* transaxle? Assume that the chassis would be designed around the engine/trans combo, so the spacing isn't as big of a deal as trying to fit a engine/trans into pre-defined space.

I've heard mention of the Getrag 6spd (audi?) and the p-car 6spd (what years?) but is there anything else that is cost-effective? I'd rather not dump 20K on a sequential box or anything like that [img]/ubbthreads/images/graemlins/wink.gif[/img]

Worst case, I will have to use one of the audi-boxes in my test, but I was really wanted to get the 6spd in.

Thanks
James

Mark Worthington · 03-24-04, 04:21 PM

Well, aside from the Audi 01E and the Porsche 6-speed (which, like the Audi, is also manufactured by Getrag), there are the following:
[*] The Quaife 6-speed. Not sure about availability. The early ones had problems and they went back to the drawing board. Price would be around $15k. Ouch.
[*] The RBT 6-speed. Essentially a new ZF. Cost would be about $15k.
[*] The Ricardo 6-speed going into the Ford GT. Not yet available (but should be soon), weighs a lot more than a ZF or a Getrag, and can handle 600 hp in a 3300 pound car.
[*] The Corvette C5 / Z06 6-speed. Too big for a GT40 and would need to be adapted from torque-tube configuration to standard clutch setup. Capable of handling lots of power. Cheap - I saw the one in the attached picture go for less than $500 on Ebay a couple months ago.

MadMaxx · 03-24-04, 05:05 PM

I considered the C5 transaxle (well...it's kinda a transaxle hehe) but I think it will push the engine too far forward. The car in question is dimensionally simmilar to a GT40 in size and wheelbase (slighly longer) but it's still in the mockup stage.

On the Audi 01E, how much are these going for?

This is a pic I found of a LS1 bolted directly to the C5 transaxle, in case anyone was interested.

James

Howard Jones · 03-24-04, 06:20 PM

That well never work in a GT40.

Mark Worthington · 03-24-04, 06:24 PM

[ QUOTE ]
On the Audi 01E, how much are these going for?

[/ QUOTE ]

A new one would set you back about $6,000, shipped from Germany, probably a little more right now due to the weak dollar. There's a used one (120,000 km) on the German Ebay site right now for something like 1,200 Euros.

MadMaxx · 03-24-04, 08:28 PM

[ QUOTE ]
That well never work in a GT40.

[/ QUOTE ]

Like I said, it's not going in a GT40 [img]/ubbthreads/images/graemlins/smile.gif[/img]

But, just looking at the pic, the trans tip to centerline of the half shafts is about 30" or so. Total, there would have to be 4'8" worth of engine bay just to get the combo to fit. Don't see that happening.

Audi 5spd will most likely be what goes in.

James

Eric · 03-24-04, 09:38 PM

Porsche 993 and 996 6 speed boxes can be had anywhere from $1500-$3500 and they can handle alot of power, are easy to find, and have infinite gear possibilities. See this thread for applications.
http://www.gt40s.com/ubbthreads/show...b=5&o=&fpart=1
Also, i dont know how the 01E ring and pinion sizes up but the 5 spd 016 ring and pinion are tiny especially compared to my g50 20. And the ring and pinion is supposed to be the WEAK part of the g50 series transaxles.

JP · 03-25-04, 04:06 AM

Use a product that is proven.

The Renault box with Quaife internals is PROVEN to withstand 500HP. Paul Thompson, Roy Smart, Dave Parker, Derek Bell all use this combination.

It is cost effective too. AND lightweight compared to a ZF or similar box.

Kevin Jones of GTO engineering will also be supplying a 6 speed set of internals shortly. Comprising of straight cut gears.

The details(again [img]/ubbthreads/images/graemlins/crazy.gif[/img])

Derek Bell: www.bell-performance.co.uk

Kevin Jones - GTO Engineering : 0118 940 1101

Kevin also provides a Quaiffe made LSD.

Regards,

J.P

Kalun D · 03-27-04, 03:07 AM

Before you spend major bucks on a 6 speed look carefully at the ratios. Some are for narrow powerband cars. I just rebuilt a 6 speed in a S2000 Honda, it has the same ratio spread as a typical 5 speed, just one more gear in between to take advantage of the higher HP narrower powerband on the 4 cylinder in that car.

Something like this would be useless in a 40 with a wide powerband V8, you wouldn't be making use of the entire powerband between shifts.

6 speed is OK if both 5th and 6th are overdrive but it would be nice to have an autobahn or race track to make use of it.

Robert Logan · 03-27-04, 06:42 PM

We are running the OIE (6 speed ) boxes in our cars and one of them has covered more than 10,000 km. since it was installed. The ring and pinion are about the same size, the gears are wider by a factor of almost 30% and the shape of the box and the strength around the bearings is much better. The OIE is basically a very strong box but better still the parts to fix them if required are available.

Regarding the 993 / 996 boxes these are very similar and with some good engineering (now I am sure that will spur on some of you out there) it could be fitted into our cars. With a cost as stated above than they would be an economic and viable alternative.

Best wishes,

Robert