I broke down and bought some new moly single piece retainers, VS95 springs and hardened keepers from JM. All of the installed heights had been previously measured using stock retainers and keepers. With the new hardware in place installed spring height jumped a bunch. Two springs on one head took .060 spacer, and the rest .090 to get to the area of 1.765. Is this what should be expected? Using stock retainers and the same valves, in each hole, height came out to 1.78 to 1.90 if I remember right (figures are in the barn).FYI. One of the retainers apparently was bad. Its collar was less than half the thickness of the others, .049 vs. .116. It has been returned for an exchange.
After getting the head assembled the chambers were cc'd. They are all 66 to 66.5. This works out to a CR of 9.2 to 9.25. With a mild Isky E-4 set straight up, 1.43 rockers, should the centrifugal advance be limited to help with detonation? We are forced to use E-10 here. Perhaps the alcohol will make detonation a non issue?