Can you get decent oil pressure with 0.013" main bearing clearance?

Evidently the answer is yes!

Short version - fairly mild 440. Had a Mopar builder put it together. They screwed up the top end of the motor but I fixed it. Motor always made a noise. It had very little run time. Finally the car just began to shake real bad in gear - came on fairly suddenly. I thought it was in the tranny or converter - it wasn't. Took motor apart - found bad piston pins (galled).

Bought new pins and had a local Mopar racer put it back together. He found that the motor had a 0.010" under crank with standard bearings!

I was wondering why the oil pressure was fairly low at idle............

That sux!

I made a similar mistake on my old 1955 Dodge D500 17 ft. flat bed, it had set for a long time before I bought it and I drove it for several 150 mile trips into the San Bernardino Mnts. from Joshua Tree,CA, The 254 C.I. straight flat head six it would have real low oil pressure when hot and idling, I tried changing the rod bearings thinking the motor was stock and put stock size rod bearing in it, it had a .010/.010 crank in it It knocked like crazy as soon as I started it up, luckily it didn't spin a rod bearing idling in my drive way so I took the old rod bearings to someone who knew a little more than I did back then and got a set of .010 rod bearing and did that job again with a lot better results
Live and learn

Wow! Surprised it wasn't more noisy!

Reminds me when a friend tore down his SBC for a rebuild. It was in a pro street style jeep wrangler w/ a blower on it. Ran mid 6s in the 1/8.
It had .030" over pistons in a .060" over block. He had bought it years prior as a complete long block.

My son bought a 340 Duster. Ran great, pretty much stock ,13.30's. Sold the motor and the guy who bought it took it apart. .010" under crank with std main bearings.
Doug

Buddy of mine put std bearings on a .030" under crank in a 360. It didn't have much oil pressure when it warmed up.

SMH. The things people get away with.

The first engine I built by myself was a 383 for a 71 RR I had at the time, this would've been around 81 or so. The crank was bad so I got one from my cousin and took it along with the block to the machine shop. They were supposed to polish, mic and order the correct bearings for it. After it was all done I picked up my parts and after a good cleaning put it together. At the time I didn't own any mics so I just screwed it together without even using plasti gauge. The engine started right up and had pretty good oil pressure, but when it warmed up it started knocking. The knock wasn't in the front or the back, it was everywhere, plus the oil pressure had dropped way down. So I pulled the engine out and apart to find the crank was .010/.010" and they gave me standard bearings. My Dad had done business for years with the machine shop and they were good about taking care of their mistake. They polished, miced and got the correct bearings for another crank, plus furnished me with another complete set of Fel-Pro gaskets. After that little experience I stepped up to plasti gauge. lol

Anything I could say would just make everyone mad.