well ive ordered most of the parts for my 4th rebuild in the past year (dont ask). i already have the crane 272 cam and im going to be using the commp cams 1.6 roller tip rockers. ive called crane and talked with the guys there. the conclusion has been that i need a different spring than what is suggested for that cam. the suggested spring for that cam and 1.5 rockers is the crane 99848. this spring has a max lift of .487''. while using the 1.6s the lift on the exhaust will be the highest lift at .512'' lift. after some calcualtions and some searching the crane tech blurted out the best spring for me, the 99846. same dia as the 99848, install height of 1.8'', 125lbs seat pressure, and max lift of .640''. perfect...except for the price...$165 from summit, and theyre on back order! so i ordered them. what else was i going to do?
i also did some research on the valve to piston clearance minimums.crane suggests .150''. i did some looking on
www.60degree.com and found one individual with a supercharged 2.8 s10 using the crane 272 with 1.6 rockers and flat top pistons, and claims no problems. i will be measuring my clearances just in case. it was also said that the iron heads valves are recessed over .5'' into the head and that helps the valve to piston clearance.
jsut throwing this all out cause ive heard a few were asking questions about this subject.
questions?
