Am I in for problems using the 01E?

[Darrin]

I was told by a vendor (not mine) that using the "Audi unit will result in poor half shaft angles and elevated engine height" in the GT40.

Is this what people who are running the Audi are seeing and is it causing issues?

I like everything I see about the Audi and know what and from whom I will get it (Steve) if I go that route, but if it causes issues with respect to the engine height or shaft angles then I may end up going with a strengthened Renault UN1.

 

[David]

Yes it's true but that is exactly the same problem with the UN1!

My sump is about 20mm above the bottom of the chassis with the 01E 3mm off the chassis and my half shaft angles are within acceptable limits for a low mileage car, I don't expect to get the same 200k out of the CV joints that I would out of a 'common' car!
I'm not quite sure where the 289/302/351/coyote sumps sit in comparison though, it might sit below the chassis at the same height of engine.

You can at least flip the UN1 which you can't do with the 01E but it'll cost you a fortune to get a UN1 up to taking the same kind of torque as the 01E will handle 'out of the box'.

IMO forget the UN1, either go 01E and accept its limitations or go straight for a G50, ZF, RBT etc.

 

[David]

Actually I take that back, the latest '027' UN1 is rated to 400Nm, the 01E to 450Nm so maybe not that dissimilar. The '016' is I believe only 300Nm though.

Also see http://hollowayperformance.com/Brochure August 2011.pdf for 'uprating' the UN1, $3900.

 

[Scott]

I was told by a vendor (not mine) that using the "Audi unit will result in poor half shaft angles and elevated engine height" in the GT40.

Is this what people who are running the Audi are seeing and is it causing issues?

I like everything I see about the Audi and know what and from whom I will get it (Steve) if I go that route, but if it causes issues with respect to the engine height or shaft angles then I may end up going with a strengthened Renault UN1.

it's all how the engine and transmission are mounted in relation to the chassis. A great many GT40 replicas have used the 01E with good results.

 

[Darrin]

it's all how the engine and transmission are mounted in relation to the chassis. A great many GT40 replicas have used the 01E with good results.

Yes and it looks like the UN1 has the same issues. The G50 is an option but at about twice the cost and I'd rather not spend that much on it.

BTW, I meant you Scott not Steve in my initial post.

 

[David]

I think the UN1 is slightly better in that the output shaft is closer to the centre line but there's not a lot in it and it is still below the centreline rather than above like the ZF/RBT and (flipped) G50.

I think the UN1 might also be slightly better in that its either narrower or higher than the 01E at the point of the output shafts so it fits either lower or between the rear frame rails rather than the 01E which is limited by them as in this picture.

 

[James]

Do you think the angle on the CV joint would be higher than 20 degrees if the engine was mounted in the standard location (say an LSx mounted to an O1E)?

 

[Eric A.]

If you aren't running a dry sump and the bottom of the oil pan is even with the bottom of the frame you should have no problems.

 

[James]

Eric,

Not sure what difference it makes, but I have an SLC, not a GT40. So I'm not quite sure what "normal" engine height of a GT40 is compared to that of the SLC. In the GT40, does the engine oil pan run even with the frame? Also, I have heard LS(x) oil pans are very shallow, if the oil pan is even with the frame, would it make it too low. Also, I believe the tire/wheel combination on the SLC is a bit taller.

Trust me, it is not my intent to question your opinion, quite contrary, I would like nothing better than the Audi transaxle to work without having to raise the engine up above where it is normally mounted.

There are a few sites I have seen that you can get high angle CV joints that work with up to 20 degrees of angle without binding, and can for short moments go up to 40. If so, that would definitely solve the high angle issue

I see a ton of pros using the Audi Transaxle

Low Cost
6-Speed
Availability
Gearing - Especially if you look at the diesels
Torque capacity - diesels again

 

[Fran Hall RCR]

James.
the RCR40 is based on an original car and we ahve to raise the engine by 1 1/2 inches to make the Audi tramns work...and even then the driveshaft angle is still around 10 deg.

The SLC has longer axles as the car is much wider track ...this decreases the angle of the shafts but not by much.
You will have to raise the engine as high as you can, while keeping clearance between the intake manifold and the rear window...this then creates an issue with the intake tube being crammed against the rear window.
The knock on effect is that you will now need a custom adapter plate that has the chassis mounting holes relocated lowr to pick up on the chassis mounts.
The driveshafts and shifter will also need to be custom too.

Some German spec diesel Audi transaxles have a large 10 inch rp and can take big torque and power but they are super rare and were a one year only model....