First post...try not to beat me up too bad!

355 SBC, fresh build. Only thing NOT new is the block. Block was line bored/honed/cnc squared off the mains and bored .030/decked to 9.000. It an old 1969 010/020 block, 2 bolt with ARP studs. Machine shop installed cam bearings with lube holes in at 3:00/7:00 (dual hole brg), not sure what bearings they used.

Rods mic'd out at .002-.0022" (king race bearings)
Mains .002-.0025" front to rear (sealed power HP coated series)

After 30-40miles, mains are now at .003-.0035"

M55HV pump with pink/purple spring. MSD billet dist with O rings removed. Front lifter galley plugs removed, tapped and allen plugs installed. Center plug is flush so not too far in. Block deburred and lifter valley return hole flash removed.

running straight 30w oil.

cold pressure idle in P is 60#
170-180f idle pressure in P is 38#
Idle pressure in gear 25# (1000rpm idle)

After a hard run (7400rpm pull), came to stop and 0psi oil pressure. confirmed with dummy light on dash and autometer mech oil pressure gauge. Brought engine up to 1900 = 20-22#

Cruising under stall 2200-2800ish 38-40# of pressure. Stop again...0psi.

Pulled motor out, pulled main caps bearings look great. Pulled all the rod caps, pushed piston down to check thrust side insert...look brand new. Pulled pump plate and gears, poured oil directly into pump output port, pressurized with 70psi of air pressure, no gurgling or obvious leaks. Once all of the oil has been pushed out by the compressed air, can feel air coming out between main caps and crank counter weights. Checked pr valve in pump half, seems ok, wasnt stuck and didnt have any trash in it. I have not pulled the cam yet, was trying to minimize down time and cost of course. HG for this motor are not cheap (have to have .051"). Any ideas? Im about ready to pull the intake, valve train, and see if there is something wrong with the cam bearings. Figured they would hiss with compressed air if they were whooped. Running out of options at this point. Blocks never been froze or overheated since ive owned it.

Im leaning towards cam bearings as my springs are set to 220# seat pressure and not sure what bearings the machine shop used.