GT40s.com - View Single Post - swap 944S2 pinion and ring 083F in 951 gearbox 016R help

Pete T · 01-16-08, 01:53 PM

I wouldn't expect this to be a problem. The 8:31 is much stronger than the 9:35 (3.888) used in the earler transaxles. It should be comparable to the 951 non "S" set. The turbo S is the only on that was shot peened.

The 9:35 is the same gear set as the one used in the AUDI 016. The 8:31 is much stronger. As I said earlier, it is larger in diameter and has wider and thicker teeth with a larger tooth contact area. The difference between the 9:35 and 8:31 is probably something like the difference between the 915 early gears vs the 8:31 late set except on the AUDI based one the ring gear is also larger in diameter.

I would expect the same durability with the 8:31 gear set as the standard 8:27 951 gear set. The Porsche factory training manual states that the reliability of the S2 transaxle is equal to the 951 transaxle.

You could always get the set cryo treated before installation. The biggest killer of these transaxles is overheating and drag race starts. There is a guy on the 944 v8 board that has a 944 with a Chevy LS1 with a Magnuson supercharger. He hasn't been to a dyno but suspects 600+ HP at the flywheel. He is running a stock non S 951 transaxle with cryo treated gears. He runs on the street and also quite a bit on the track. He hasn't had a problem yet although it has only been one season.

01-16-08, 01:53 PM	#7 (permalink)
Pete T PeteT Rookie Join Date: Sep 2006 Location: Wheaton IL GT40: none Posts: 82 Rep Power: 3	Re: swap 944S2 pinion and ring 083F in 951 gearbox 016R help I wouldn't expect this to be a problem. The 8:31 is much stronger than the 9:35 (3.888) used in the earler transaxles. It should be comparable to the 951 non "S" set. The turbo S is the only on that was shot peened. The 9:35 is the same gear set as the one used in the AUDI 016. The 8:31 is much stronger. As I said earlier, it is larger in diameter and has wider and thicker teeth with a larger tooth contact area. The difference between the 9:35 and 8:31 is probably something like the difference between the 915 early gears vs the 8:31 late set except on the AUDI based one the ring gear is also larger in diameter. I would expect the same durability with the 8:31 gear set as the standard 8:27 951 gear set. The Porsche factory training manual states that the reliability of the S2 transaxle is equal to the 951 transaxle. You could always get the set cryo treated before installation. The biggest killer of these transaxles is overheating and drag race starts. There is a guy on the 944 v8 board that has a 944 with a Chevy LS1 with a Magnuson supercharger. He hasn't been to a dyno but suspects 600+ HP at the flywheel. He is running a stock non S 951 transaxle with cryo treated gears. He runs on the street and also quite a bit on the track. He hasn't had a problem yet although it has only been one season.