Audi transaxle questions

Hello,
I apologize in advance for the off topic question, but you guys are the only people I can find online who are doing "mad scientist" stuff with various Audi transaxles.

I have a 1951 Citroen Traction Avant that I'm converting to electric. Its front wheel drive. The stock transaxle was weak when it was new, so I'm looking to replace it.

I'm hoping that an Audi 01A or 01E will fit, but I need dimensions to confirm.

Can anyone help we with the following rough(ish) dims?
Total length
distance from bell housing to drive shaft centers - and then to front
width across widest point
width across mating surfaces of the drive flanges


The transaxle extends forward, through a steel cradle that forms the front suspension mounts (which I want to keep). The drive shafts pass through it also, so I'm limited in my width. The stock transaxle is around 8 1/2" across the drive shaft flanges.

Thank you for any assistance.

Pete

TA Side.jpg



Front engine bay.jpg


Engine Compartment.jpg


TA_TransaxleSpacing.jpg
 

Randy V

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Welcome to GT40s.com Peter! Interesting project you have there. I’m sure someone here has the knowledge you seek...
 
Thanks Randy,
I'm hoping someone has one in their garage that they can put a tape measure across.

The measurement I'm most interested in is the flange-to-flange distance. If one of them is close then I'd probably go get one on the hope that everything else would fit.
 

Randy V

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Thanks Randy,
I'm hoping someone has one in their garage that they can put a tape measure across.

The measurement I'm most interested in is the flange-to-flange distance. If one of them is close then I'd probably go get one on the hope that everything else would fit.

I thought I remembered someone posting a Dimensions Picture sometime over the last few years or so...
 
Mounted in that position the 01E will run backwards so you will have 6 reverse gears and one forward. Try a Porsche rear engine transaxle.
 
@Eric. Good to know. I'm running an electric motor. I'm relying on the specs that say I can run it just as fast backwards as forwards.

@Randy. Thanks I've been searching though. I've found 2 that have side (length) views and dimensions - so I'm probably close enough there. I haven't seen anything yet showing dims across the flanges - which is my critical measurement. I'll keep looking though.
 
Given the ratio of reverse gear you will have to run the electric motor pretty fast to get up to highway speeds. Also you will be running the ring and pinion on the back side which is not good for longevity. Look for a 996 transmission. About the same size as the 01E and would work better.
 
Hmm. Yes- I had mistakenly thought that I could solve the problem by running the motor (and so transmission input shaft) in reverse.

I think I understand now. The problem is that the diff is effectively spinning the wrong way - while the input shaft spins correctly. I'ts probably not kosher to reverse the input shaft direction.

I'll look at the 996 unit. Thank you.
 
It's not a great idea to reverse the rotation on a gearbox with helical gears, as the gear thrust pads are on one end of the gears. Reverse rotation will thrust the gears in the opposite direction where there is inadequate surface area to handle thrust forces.
 

Randy V

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It's not a great idea to reverse the rotation on a gearbox with helical gears, as the gear thrust pads are on one end of the gears. Reverse rotation will thrust the gears in the opposite direction where there is inadequate surface area to handle thrust forces.

Not to mention that the heal of the gear teeth are not meant to take as much torque as the face of the tooth..
 
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