When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
What is the function of the circlip? My 86.5 has the notch but no circlip. Would placing a circilp on my drive shaft help eliminate the drive shaft movement that causes TBF? If so why didn't the porsche factory install a circlip on the 86.5 drive shafts? I have checked my flex plate for stress, and end play two times and I have not found any problems. The next time I check them I would like to add one of Constantine clamps and or the circlip. Any thoughts on this?
Ray
The circlip shimming process has been described as complicated. Its in the WSM. I thought one of the real knowledgeable folks here said it is possible to fit circlips on 85/6.
I have an 84 USA car with a Constantine clamp pinning the 84 driveshaft /TT and its all connected to an 89 auto transmission.
So yes, you can add the Black Sea/Constantine clamp, but you need to take the time to drop the rear cross member and remove the trans / TT so you have enough access space in front of the TT to install it. I think its worth it.
Are there nuts behind the flexplate for the clamp bolts or a threaded disc?
That Constantine clamp is very nice and now that there is a side by side pic, I would venture to say that if the factory 928 clamp is not balanced at the factory then the high RPM would cause the vibrations needed for it to walk the shaft.
Not for my 948 swap, Just a modded Moroso pan to clear the X-member.
As for the 928 TT, i don't see the shaft walking forward due to the thru-bolt mentioned earlier unless a bearing is coming out of its seat somewhere in the rear.
The Vette C5 remedies this by installing large TT bearing circlips inside the TT.
What I believe is causing the 928 flex disc to walk forward is good old fashion high RPM vibration at the coupler and shaft that would take the most force throught the automatic drivetrain and the reason why the flex disc moves forward in relation to the stationary shaft is the centrifugal force pulling it that direction just like Pressure Plate tines in a clutch system. It's debateable but no matter the mechanism it is happening and and Like Forest said...."That's all I gotta say 'bout that".
Thanks for all the replies, you guys know your stuff
If anyone can confirm The Automatic TT's having a 30mm length difference, please let me know.
Hey everyone...resurrecting an old thread here with a question...for the clamp that goes around the outside of the torque tube to hold the exhaust hangers...I lost that hardware and am collecting the assembly again in anticipation of some exhaust work..
Can someone provide the diameter of the torque tube so I know what size T-band clamp to get? The Porsche part no. 999 512 325 02 is nla and 928Intl doesn't have them either so looking for that outside diameter so I can get a generic one...
Hey everyone...resurrecting an old thread here with a question...for the clamp that goes around the outside of the torque tube to hold the exhaust hangers...I lost that hardware and am collecting the assembly again in anticipation of some exhaust work..
Can someone provide the diameter of the torque tube so I know what size T-band clamp to get? The Porsche part no. 999 512 325 02 is nla and 928Intl doesn't have them either so looking for that outside diameter so I can get a generic one...
Appreciate any help guys.
Below is a pic of the part...
100mm clamp with an 8mm bolt that draws it together. There's probably 15-20mm of space that the bolt takes up.
I've got a small box of them replated, if you decide you want to use the proper part.
Semi-retired, as of Feb 1, 2023.
The days of free technical advice are over.
Free consultations will no longer be available.
Will still be in the shop, isolated and exclusively working on project cars, developmental work and products, engines and transmissions.
Have fun with your 928's people!
10-08-2010, 02:41 PM
