[MartyVi]

Originally Posted by jr1978racer

Add another vote in the "20w50 is a bit thick" column, but I don't think that's your issue.

I would be checking clearances and wear points. Regardless if this is your first or five thousandth Pontiac build, I'd tear the top end down to inspect. I'd be checking push rod to push rod hole clearance, rocker to valve cover clearance, rocker tip to valve tip geometry, spring retainer to valve seal clearance, even the run out clearances on those roller lifters.

Gaskets are a whole lot cheaper than the parts you're running the risk of ruining by continuing to run that engine with that malfunction.

Agree on the oil. Was just curious to try.
Have had the top apart 2 times now.
Checked all that you mention and all within spec.
The only issue at first start up was the Scorpion rockers rubbing in 4 places inside the aluminum Pontiac valve covers. I fixed that by using BOP one inch spacers and switched to a set of Harland Sharp rockers from my sons build.
My opinion is it’s the lifters and the high lift of the cam. .590 ish. I believe the oil band is coming close to the top of bores at full lift and bleeding oil. I have confirmed that visually by rotating the engine and priming the pump. Very little oil flow from top of bores until the lifters get to full lift then flows well but not enough to drop the oil pressure in the whole system. A better lifter might do better.
It’s not that loud but I’m kind of picky. Would like the pass side to be as quiet as the driver side.
Thanks

[chuckies76ta]

Not sure if this is of any interest to you with your build, My builder did this little mod to the feed hole on the Crower lifters that I used. Also, my lifter bores are bushed so it's a bit of a different build. Mgarblik did a post about this same issue with lifter oil band.

Charles