[olddog]

High rpms is what stretches rod bolts. They only stretch when the forces from RPMs exceed the stretch from torqing the bolts down. If you put in good quality bolts and limit the rpm to where the bolts are not getting stretched, then they will last forever in engine life times.

High lift cams and the geometry of all those parts with heavy springs can shorten life a bunch.

A mild build could last as long as a factory engine. The more radical the build and the harder it is ran the shorter the life. Obviously a top Fuel dragster is done in a 1/4 mile. You should be somewhere between and closer to a factory engine than a top fuel engine.