Little background info. Gauge used for testing was an autometer cobalt electric oil pressure gauge. Full sweep

On the stock motor the oil pressure hung around 20psi at idle and 60psi driving when fully warmed. Added an oil cooler with the turbo setup with a sandwhich adapter. Oil pressure dropped a little but was still about 15-20psi at idle and 50psi driving.

On the built motor the oil pressure has never been as good as stock. First used a topline oil pump, oil pressure would drop to as low as 10psi at idle when really hot and driving oil pressure stays around 40psi. After about a year I had to replace a bent rod so I changed the oil pump also to a melling oil pump. Oil pressure didn't really change.

Wanted to bump up the pressure up a little since it can drop to about 8-10psi at idle on hot days.

First test added a .200 washer under the spring. Oil pressure went to 80psi at idle, this was cold. Way to high so tore it back apart and changed to a .050 washer. Oil pressure seems to have bumped up a little bit but nothing really significant. Probably should go to a .075" washer and may have better results.

Figured I would post this up since I never found any on here. Comments?

this may or may not damage turbo oil seals from increased pressures. Oil restrictor may be required.

Yea Im aware that this could be an issue if the pressure gets to high. But with the pressure I am seeing now they seem to be perfect for the holset.

80psi brand spankin' cold is not THAT bad. I get 75 on the cold start with the 420a turbo. She falls down pretty quick.

But, more importantly, what's your theory on the low oil pressure after the rebuild? I'm not real confident in the melling pumps for our cars. Oem stock seems to be the way to go. Did you upgrade to the new pump when you did the rebuild? Generally with a rebuild, your pressures come back up from where they were before the rebuild.

I have no idea why the oil pressure dropped with the rebuild. I put a new topline oil pump in with the rebuild and figured it was just POS and it was doing some weird things so I changed it after a year to the melling. Nothing really changed though. The sender is T-ed off the oil feed so that may be giving me a lower readings somewhat but thats always where I took it from.

Im just thinking at this point that the OEM oil pump is probably the best out there