915 Diff / Rack & Pinion set up

[jomalkay]

I have read many threads relating to this subject with tons of good information, thanks to all. Do have a few questions, thought best just to start a new thread.
Rebuilding a 915 box, new GT Diff, bearings including the pinion and diff carrier bearings, amongst many other new items. Box is from '85
1) The pinion depth is marked 66.72 (on the ring gear) and the original pinion shims totaled 0.75mm. Porsche manual said not to exceed 0.5. After first pass setting the depth, i will be at 0.50 - 0.55mm total shim thickness. Talked to several collegues and they have never seen a setting that big, 66.72, but it is what it is. I made the setting tool with dial indicator inside of old diff housing, will verify the tool on CMM for final check.
Question; Have others seen a depth of 66.72+ and will it be any problem using total of 0.55mm shims?
2) Diff preload - i have also changed cover plate to use factory cooler, measurements are with new GT diff and cover plate. Started with shim stacks as they were originally set, gradually increasing betwee 0.05 / 0.15 on the cover plate side. Using old bearings, but they are in good shape, honed out to be a light press fit for easy removal during setting. Also checked the "pointer" type torque wrench against a certified click type and verified correct.
Measurements shim stack / continous movement in inch lbs torque / static torque
a) 3.15 / 3-5 /15-20
b) 3.30 / 15-20 / 30-35
c) 3.35 / 20-23 / 30-35
d 3.45 / 35-40 /60 (seems very tight)
Questions;
- I am assuming the torque setting is for continious movement? difficult to measure in a smooth action or is it actually static torque?
- Going from 3.3 to 3.35 made little diference, at 3.45 was big difference. Should i error on the side of loose or stiffer? I will be replacing with new bearings (SKF), test berings are SKF as well.
- does this shim stack sound high?
- Prior to torque test, i measured with feeler gage last (3) settings were in the tolerance stated from manual. I find this somewhat subjective as the cover plate has interference the last bit, i just tightened down until i did not see / feel any slop in the bearing to race fit, again, found this to be very sublective. Is there some tricks to this or if i am using torque wrench as final measurement, do i even need to worry about this at all?
3) when i get to backlash check, do i align the single mark on the pinion in between the two similar marks on ring gear?
Thanks in advance, John

[jomalkay]

Bump

[rs-vic]

I’m currently rebuilding a 1976 915 where the pinion depth N marking is 43 which would be 66.73 and I need a shim thickness of 0.6mm

[PeteKz]

Old posting and incorrect name. restart a new one with "915 ring and pinion set up."