Calypso

iTrader: (1)

Hey guys, we were seeing ~15psi oil pressure at idle and no more than 30 or so while driving. That was on VR1 10-30. I called the machine shop and they said they left the main bearing clearances a little looser, due to my horsepower estimates (1K flywheel).

So we switched to Brad Penn 20w50 and now I have 20psi at warm idle, and up to 40-45 while driving. Is that enough?

I'm thinking I should get a melling high-volume pump, but also read they suck the stock pan dry.

Advice??

Twin turbo c5

My corvette stays around 40 psi when driving with 10w30 Castrol. So that sounds about right. Run it!

IMPATIENT 1

If more psi is wanted why not just shim the oil pump spring alil? I shimmed a new stock 5.3 gm pump and have 40-50psi at idle 75-80psi wot, cruise with 65ish psi..i fed the s480 with a unrestricted 4an and returned with a 10an..switching to twins for this coming season and if i dont have the psi i wanted ill shim pump spring till i do.

Calypso

iTrader: (1)

Already shimmed.

IMPATIENT 1

Dang. im sure yours will be fine with a heavy oil. i have hell getting my oil temp up so psi is always pretty high.lake water cooling the block with a 8qt pan makes it tuff to build oil temp prior to a pass.when i race this spring i wont be able to start my engine until im about to leave the rope

itsslow98

iTrader: (18)

Its funny you mention this because I broke my new motor in(4.6 not an lsx) with sae 30 non dtergent oil and the oil psi was 25+ at idle. After 600 miles I switched to 10w-30 VR1 and now Im at 12-15psi at idle. I wonder if there is a correlation here.

Calypso

iTrader: (1)

Maybe. Depends on your bearing tolerances I guess. Mine are looser than stock for sure. I'm more than likely going to do a HV pump just for peace of mind...just wanted advice on which one and whether anyone runs them successfully with a stock pan.

itsslow98

iTrader: (18)

I ran Melling 10296 pumps in two of my cars and never had an issue. Rule of thumb is 10psi for every 1,000rpms.

Calypso

iTrader: (1)

Thx. Yeah I know that standard from the old sbc/bbc days, but most of the LS crowd says they have 40..50..even 60psi at idle. My engine book says LS motors have tighter bearing tolerances than sbc/bbc and thus require higher oil pressure.

Anyway, I'll just grab a 10296 and give it a try. Thanks!

LS1x2

iTrader: (11)

I see 15psi hot at idle. Goes up with rpm to close to 50psi IIRC at the shift point. Maybe 1500 miles on it but a I'd guess 200-300 pulls. Had a long conversation with the builder about it, and he convinced me it wasn't a problem. You are moving the same volume of oil that that pump always moved. I don't think you are seeing a scenario where the bearings aren't lubricated, which is what matters. Runnin castrol 20w50 and changing it probably more often than necessary.