The Guy in MY 99TA

I was just wondering when a large hyd. roller is used should the lifter bores be sleeved then also? I know it is supposed to be done with solid rollers, just wondering about a hyd. roller. I want to run a larger type of hyd. roller, something like a 244/252 with a 115lsa. Maybe even larger.

Josh S.

racer7088

No you really do not "need" to do this unless you have lifters that lose oil pressure when they go really low in the bore from a lower base circle cam or unless you are trying to tighten up lifter clearance and reduce oil flow through the bigger stock lifter clearances on the aluminum block. They also make better designed lifters like the Morel that have a little more lifter travel at the bottom until they pop put and lose oil pressure if they go to low as compared to stock. People also run a lot smaller oiling hole on th bushing so if a lifter does pop out it wont kill all oil pressure as fast as the stock ones would. The stock OEM LS1 lifter retainers though keep the lifters from popping out of the bores usually anyway.

BTL FED

iTrader: (9)

What he said, before you would need to sleeve the bores if you were running a large solid roller with the crane solid roller lifters because once the lifter went up so far the crane lifter would allow oil to pass by it causing an internal oil leak. But with the morals this is not an issues anymore. the duration has nothing to do with the oil pressure loss it was all in the lift, I believe once you got over .700 lift is when the problem would start happening

racer7088

The lifters do not go up any further in a higher lift cam. They only go down further or start out lower on the base circle of the new higher lift cam. The base circle is reduced or "lowered" to get more lift. The lobes can not get any taller or you could not put the cam in the motor. When the lifters leak at the top or the bottom of the lifter body it is usually when they are lowest in the lifter bore as in on the base circle. At full lift all the LS1 stuff is only "up" so far so it virtually in the same position in the bore at full lobe lift.

Generally if a lifter leaks oil pressure at the top of it's travel it will do that with any cam including the stock one.