I just cut my Isky's. Been running them 9 years. But this year we tightened up the lifter bore bushings. I didn't like the oil flow with the reduced clearance. Especially the intakes as the pushrod oil feed hole is offset and never lines up with the bushing orifice. I made the notch deep like .020". Is it to big? My theory is the restriction before was the pushrods. They are restricted with roll pins as the inner diameter was .107" This has worked for years. Well see soon.
Doug