I have just finished building a mild 350 . New style block 1pc seal, new rotating assembly with .275 dome pistons, pro comp 210cc aluminum heads, 1.6.1 roller rockers, stud girdle, comp cams xr264 roller cam, noisy gear drive, holley dominator intake , holley 670 street avenger carb , melling high volume oil pump, 1pc oil pump shaft, stock hei with accel super coil . Also none of the stock gauges work accept tach. and gas gauge . Temp, oil press, and volt gauge is aftermarket mechanical type except for volt gauge. When cold oil press. is 40psi after about 10 mins. idling or in gear it is 5psi or 10psi at 1100 rpm. Is this okay with regular (not synthetic)mobil 1 10w40 oil ? When you rev it , it goes to 50psi at most even if you go to 6500rpm.

 

incorrect tolerances

 

what needs to be done ? Block is stock bore. Crank and rods stock length and stroke.

 

It really sounds like you have too much gap between the crank journals and the bearings. I'm pretty sure .0018-.002 is good and tight for rods, and .002 for mians. That's just from memory, so don't quote me.

Just so you know, 50 psi hot is not really horrible unless the car will see race time.

 

who assembled the block?

Don't run it anymore until you figure it out or you could end up spending a lot of money.

 

that's lot for a high volume pump.
Did you turn the crank? what bearings?

and what on earth is up with that engine?? It seems like you couldn't decide if you wanted a full on race engine, or a truck engine to tow your boat, so you compromised and went 50/50 on it?!?