I have a 1986 318 roller cammed motor. I want to use a non roller cam in it, but the standard hydraulic lifters for it won't cover completely the longer oil hole of the roller lifters, and therefore I get very low oil pressure. The engine is a brand new rebuilt. Any suggestions on how to resolve this matter? Does anybody make longer lifters to compensate for the shorter standard hydraulic lifters? I didn't realize this problem until I had the engine all together and ready to drop in.