What side clearance are you setting the rockers at? Too much clearance will also drop oil pressure. I shoot for 0.015 inches and make sure a 0.020 inch shim don't fit. I use a u shaped SS shim.

I run a .065 restrictor in the tee before going to each head. Tried a .075 and immediately flooded the heads and pushed raw oil out the breathers. I run 400 seat pressure, 1.6 HS rockers .810 lift with NO problems for years.

RIP

I run a .060 restrictor through the standard block oil holes but they have been drilled and fed from the galleys for full-time oiling. The top end gets loads of oil and I get 25 lbs of pressure priming with a cordless drill. I have yet to fire the motor but I think I could have afforded to go with a smaller retrictor. This is with a standard volume pump too.

I used Holley carb jets (#48) to restrict the oil flow to the top end. Run 5W-30 oil. Engine oil pressure is 16-17 Psi at idle and about 70 Psi at WOT. (The jets have a 1/4-32 UNF thread)





/Tom

Thanks for this helpful thread, I did the same thing using jets...
Wanted to bring pressure from 20 in gear to 35 with 20w50 oil. Turned out that 69 jet was perfect fit.