Quote Originally Posted by DennyW
I agree. If it's a stock build, and running stock clearances, you don't need a HV pump, but, it won't hurt either, because a stock build is not usually driven hard anyway. The oil restrictors is what gets me. Why would someone want to starve the upper side from nice cooling, lubricating, save my springs oil ?
My understanding on the Olds 455 restrictors is that they help the bearings to live in a highly stressed - drag racing - engine and the lesser amount of oil supplied to the roller rockers is sufficient.

Since drag racing doesn't create the heat loads endurance engines do this is probably one reason they get away with lesser oil flow up top.

Kinda funny that the late Buicks - 430-455 - have the opposite problem and want additional flow up top when roller rockers are used.

The restrictor bit on the Olds engines is a commonly done deal and recommended by Olds engine specialty shops.