Your oil pressure looks a lot like my JNIX 235, while one its way to spinning a bearing, after trying TWO Melling oil pumps - with no change in pressure between the two. Dang good thing you pulled the mill for a look-see, as I think you would have also been headed towards a spun bearing!

I would double-check the clearance on that Melling pump, between the gears and cover. With the gasket, you should have between .002-.0025", as per Tom Langdon. Stock gasket I believe is .009" thick. I have seen gaskets in full gasket sets measure thicker - best to check thickness. I made my own for the 235 turd motor now running in my '57 car from a file folder measuring .008". I used gasket sealer on both sides, then installed the cover and tighten the screws. Removed the cover, then cleaned up the squeeze-out inside and installed the cover for good. I did this with a GM pump and came out with BETTER oil pressure than I had with the JINX (good clearances), despite the sloppy bottom (rods -.003", mains - .004"+)!

Can you look at the cam card that came with Patrick's cam and tell us what the DURATION @.050" is? Are you looking for a bigger or smaller cam? Might be worth a call to Tom Langdon to see what he might recommend. He also might have GM oil pump gaskets available.

Sorry to hear about your bad luck on a fresh rebuild - man, I know the feeling! The JINX I speak about began with me as a $300 used 3/4-race motor with a fully ported head, Crower cam and full kit, assembled in 1978. First, the PO's builder left out the tin baffle in the crankcase for the road draft tube - I could only slow down the mess under the '57. Then, it dropped a intake valve leaving a gas station near home - due to a broken CROWER valve spring. Took the head in, only to find out it was cracked above a water jacket. I checked compression before pulling the head, #6 was 20-lbs. lower than the others, so tore it down for molly rings and rod bearings, being as clean as a home builder can be during assembly. Two years later it spun a bearing on #5.

...I'm still looking for a solid referal to a shop in SoCal that can weld up the crack to save the head.

BEST of Luck in putting it back together!

- Tim