I personally don't run that much flow however with main and rod clearances of .003 you might have to. With the help of Johnson's High Tech Performance, I built an oil system to his spec's as follows; 6.25 gpm with rod clearances of .001-.0015 and mains at .0015.002 @ 35-40 psi at whatever rpm's you want to run and an aftermarket oil filter adapter which utilizes the Ford/International diesel oil filter for the highest flow. He informed me that the formula of 10 psi for every 1,000 rpms is not applicable to the Cleveland as the higher pressure causes excessive cavitation in the oil passages which everyone knows was designed by a drunken monkey. (He supplies oil systems to several of the top NASCAR teams which include Hendrick Motorsports as well as Everenham Gillette Motorsports to name the 2 top ones.) I've run this in my wet sump stock car for the past 5 years with zero problems! No one believes me that these engines will live with that little oil pressure; they're all accustomed to 70-100 psi. Roy states that the secret to the Cleveland is the volume, the tighter clearances, light weight synthetic oil and the restrictors. Oh by the way, I do not run a stock pump, I use his single stage external pump belt driven and the quality of this pump is far superior to any stock pump due to his design and construction features. You can actually prime this engine by turning the pump by hand!! It's that good!!! I highly recommend his products!