Originally Posted By fast68plymouth
Quote:
Ok. Not sure if it was a typo or I don't quite get it lol. You said a race car would be 1.88-1.90 and the same for a street car. Should I make them all 1.9 or intakes 1.88 and exhaust 1.9?


You missed the details....... For your cam/rocker combo:
Street, Comp 928@ 1.88-1.90

Race, Comp 929@ 1.88-1.90

If you verify the spring rate of your current springs is like a Comp 928(354lbs/in), then I'd adjust the installed height to be between 1.88-1.90 for all springs.
At that rate, the spread from 1.88-1.90 should only be 7lbs.

The common shims are .015/.030/.060, so you should be able to target 1.890 +/- .010.


Ah thanks again. I read 928 instead of 929 lol. I work it out and verify my heights and maybe have a shop verify the pressures with those heights


'68 Coronet 500 w/ Indy EZ-1 headed 446, 727 trans, 9" rear
First day at the track with SUV street tires and no traction: 1.688 60', 7.24 @ 101.79 in the 1/8 mile

Great customer service from: DominicThumper Carbs, B3 racing engines, Porter Racing Engines, A-1 torque converter's, Quick Performance, Racer Brown Cams, R&R Performance, Manton pushrods