924 5 spd interchange with a turbo 924?

[EuroShark]

Will the regular 5spd 924 trans work with the turbo? Also how do you tell the difference from the dog leg and audi transmission? thanks

[running_cold924]

from what i remember, the 016Z (dogleg) has the reverse gear where 1st normally is...as in a 79 924..

[924RACR]

What he said; '80 931 and '79 924 had the snails with the dogleg first; if it's out of the car, it's immediately obvious if it's a snail:


As for the interchangeability - no, turbos don't bolt-on interchange with the NA trans. Not sure what you have to try to fit into what car, but the 81-82 turbos you're in luck, they interchange with the 944 trans (early, perhaps). For the snail-equipped 924/931, you're pretty much F'd - need to get it from that year and model, or convert to the Audi-style box.

If you have a NA 5-speed and need a trans for a turbo - please don't bodge it, those NA 5-speeds are good and useful for racing (for NAs) - please resell it to us!

[EuroShark]

Thanks for the posts, with the exception of jonny spammer. He needs to be banned

So is this a snail?

[924RACR]

No, that's an Audi box. Snails have the obvious snail scroll pattern on the diff, no bellhousing whatsoever, and the diff is behind the trans, instead of in front. They also mount differently (to the torsion bar housing) and have a completely different shift linkage.

In the two pics above, the trannies are facing the opposite direction.

Still not sure exactly what you're trying to fit into what, but hope that helps...

[EuroShark]

Just trying to figure out if the only trans that will work on a 1980 931 is from a 1980 931 or if the regular 924 will work.

[924RACR]

Ah, OK - that greatly helps me answer your question!!!

I recommend selling the orig trans/TT for parts, and swapping in the 944 bits instead. You'll need to change the torque tube, shift linkage, and obviously transmission. For simplicity, you can also swap in the torsion bar carrier from a donor 944 or 924; with the snails, as you can see in my pic, the trans mounts to the torsion bar carrier on long arms, which will be in the way. You could either cut them off or swap out that rear susp.

The Audi-style box mounts to the rear trunk floor; the holes should be there, just need cleaning/chasing with a tap.

I did this procedure on my racecar, which is a '79, and came with a busted 5-speed snail box. First I swapped in a 944 drivetrain (keeping the orig. 2.0L), which required a special clutch disk to make it work (since the torque tube shaft is smaller on the NA - 20-mm vs. 25mm). Later on I switched it to the proper 924NA torque tube and trans.

Obviously the reason is parts availability - both replacement trans and repair parts for the trans.

Any further questions on the details of the swap?

[emoore924]

IIRC, The 924 and 931 for 1980 have different mainshaft (and TT driveshaft) diameters - 20mm v 25mm, respectively. So just a tranny swap will not work. As Vaughan mentioned, you have to switch everything over to 20 mm, or everything over to 25mm...

[924RACR]

...and I wouldn't try getting away with a 20mm shaft on a car designed for a 25mm shaft...