Volume X, Issue 3, Page 78



Is there an ideal per friction clearance to run in the direct pack of a C4 for least drag/best performance?  General opinion seems to be 0.005" per friction in a drag racing application but it doesn't seem to work for me. I get bad friction and steel wear and the 2/3 shift is barely perceptible. Timing issue?

Chris Finlayson
New Zealand


Clutch pack clearances are very important, but main line fluid pressure is just as important. On your C-4, we at Mike’s Transmission would set up the direct pack at .010 per clutch, and .005 in the forward clutch pack. Depending on the torque output of the engine, etc, you will need your pressure to be about 100 – 220 PSI. Less with more power, and more pressure with more power depending on the car setup.



Mike’s Transmission
Lancaster CA
(661) 723-0081


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