944s ring and pinion for a 951????
11-27-2005, 01:52 AM
#16
Rennlist Member
The Ro is a installation/spacing measurement for the depth of the pinion shaft relative to the ring gear. Its the distance from the center of the ring gear to the face of the pinion gear. That is not an indicator of the diameter of the pinion gear or the tooth size or count. 083D Ro = 58.15mm, 083F Ro = 59.65mm, 016 = 59.65, what does the 1.5mm difference tell us with regard to tooth count or size?
The 9:35 (3.889) S pinion has smaller teeth. The pinion head for the S is slightly smaller than the turbo pinion, and it has one more tooth, so it absolutely has to have smaller teeth. Have you ever looked at an S pinion gear right next to a turbo pinion? And since the ring gear is approximately the same diameter and has 8 more teeth than the turbo, the ring gear teeth also have to be smaller.
The car that I am aware of (this was 12 plus years ago) was a standard turbo (non-Turbo S) with Authority Stage II chips, so approx 270 bhp, and was a dual use street/track car. Failed around 10k miles and broke the teeth off the pinion, ring gear survived. I do not know anyone that has installed an S ring and pinion in a Turbo in the last decade.
The 9:35 (3.889) S pinion has smaller teeth. The pinion head for the S is slightly smaller than the turbo pinion, and it has one more tooth, so it absolutely has to have smaller teeth. Have you ever looked at an S pinion gear right next to a turbo pinion? And since the ring gear is approximately the same diameter and has 8 more teeth than the turbo, the ring gear teeth also have to be smaller.
The car that I am aware of (this was 12 plus years ago) was a standard turbo (non-Turbo S) with Authority Stage II chips, so approx 270 bhp, and was a dual use street/track car. Failed around 10k miles and broke the teeth off the pinion, ring gear survived. I do not know anyone that has installed an S ring and pinion in a Turbo in the last decade.
11-27-2005, 06:48 AM
#17
Race Director
The 944S R&P is marginally stronger than the standard 944 N/A R&P. It is nowhere near as strong as the S2 or 951 R&P. Putting the 944S R&P into anything with more than 200hp is a recipe for failure.
11-27-2005, 07:18 AM
#18
Drifting
i know what the Ro is ive had to measure a few of them. two of the cars we have done in the past two years, one is my car an 86 turbo and the other is a s2, but that also had custom gear set. obviously that car has less power but it is a track car only, it does all the usual events such as targa tasmania and east coast rally. ive done about 25000 km and i think 5 track days since ive put it in, i guess we will just see how it holds up. i will be sure to tell you if it doesnt. the other car was just a standard turbo, street car. i have see the pinions next to each other in fact i have photos of it but this post will not let me upload them. (off subject but how do you make an image that is quite large take up less memory) the pinions really dont look that different in size, it the crownwheel as you could imagine that looks different. all this is not to say they will/will not fail. this is just my opinion from the experience that i have had.
