SS GIRL

i was driving my boyfriends car and when it was ideling, it was between 25-30 psi and when i was going about 60 mph, it was a little lower than 40 or at 40...

he has a ported ls6 oil pump and a new shortblock that is suppose to run high oil press also... could the o-ring on the pump fell of a little??

just mainly, can it hurt anything?? thanks

Fast SS on TNT

iTrader: (1)

Sounds like the oil pump could be failing. I have the same problem with my car. I was convinced it spun a bearing. However, at start up the oil pressure at idle is good, and it drops off pretty quickly.

Right now, I'm debating putting my new heads, cam, timing chain, and oil pump in. I have valvetrain noise. Perhaps my motor is not ruined, but my oil pump is failing...obviously much worse then your new one.

I would definitely keep an eye on that oil pressure. And use your ears as much as your eyes.

SS GIRL

when you say you thought you had spun a bearing... did it sound like this?? because the car is making a noise... read this post i started...

https://ls1tech.com/forums/generation-iii-internal-engine/157141-could-another-spun-bearing.html

Dave00C5

iTrader: (4)

At idle (hot engine) that is well within GM oil pressure specs. I would moniter it but i don't think you have anything to worry about.

Krab

iTrader: (28)

That seems a little low to me. I can't say I remember the exact number, but I think my car is at around 60 psi on a cold start up and then backs down to a little over 40 once she is warmed up. This is at idle. I don't know, 25-30 psi just seems a little low.

kossuth

iTrader: (12)

Per general automotive guidelines you need about 10 PSI per 1000 rpms. Now that is what NASCAR builders go off of so you can add alittle to that but still I wouldn't be too concerned as long as you have about 10 PSI per 1000 RPM at WOT

dazman

last car i built was a 2000 Z28 and it only had about 25-30 psi at idle and at WOT it MIGHT have gotten to 50. car now has 15000 miles on it like that and pulls hard, runs hard. with no spun bearing

mike

SS GIRL

nah im just kidding, well we don't have a spun bearing, we have a bent flywheel.....

josuemarrero

it might be the oil pressure sending unit, this is the part coming out of the block behind the intake, its a cheap part made with plastics and with time will read lower oil pressures.

LS1 JAY

My motor has about 30#'s or so at idle, and in the 40#'s while cruising and about 58# at WOT. It has about 8,000 miles on the re-built motor with a LS6 pump in it. Funny thing is that it had 45+#'s at idle when it was first re-build, but it has slowly dropped down to the new #'s. Seems to run fine and no weird noises.

Country Boy

iTrader: (24)

Forged motors have lower oil pressure than a stock one because the clearences arent as tight as a stock motor.

eallanboggs

iTrader: (1)

The "O" ring can NOT fall as you describe it. The flange on the input port neck prevents that from happening, but it could get damaged during installation. 25 or 30 lb of pressure might be enough, but if you were running 40 at idle earlier on, but now your pressure has dropped for some reason that is something to be concerned with and begs closer inspection. Your oil pressure doesn't wake up one day and decide to drop by 20lb. That just doesn't happen. It might not be something critical, but if it is you need to fix it soon. It could be the sender or the gauge. Those won't cause engine damage, but worn bearings that allow pressure to bleed off or a pump that has reduced efficiency for some reason can cause catastrophic engine failure. Don't let that happen to you.

LS1 JAY

In my case, I had the engine builder (Mike Norris @ Norris motorsports) take a look at mine and check the oil for shavings. All looks good. No one seems to know why my pressure has dropped with time, but it took a few months to happen. I don't think 30#'s is a problem by any means. Mechanical gauge showed about the same readings as the stock gauge also. Maybe it was just break in? Motor feels stronger than ever!

britick

what grade oil do you use? 10-30?

Nickn20

after a fresh oil change my oil pressure is always higher, and as the oil "breaks in" it is lower, both my cars do this.

LS1 JAY

I use Amsoil 10W-30

Black02SS

iTrader: (36)

I know it might not help, but my car idles around 40-50PSI and at WOT she almost pegs the gauge. This is with the stock shortblock (new stock crank) and a ported LS6 oil pump. Valvoline 10-30

Slowhawk

iTrader: (12)

I worked on a car recently that had oil pressure at 35psi,hot at idle.This was a built shortblock.When doing a cam change I noticed the front cam bearing moved back away from the oiling hole.Replaced the bearing with the Cam and now oil pressure is 60psi at idle.Car never really made noise just lower than normal oil pressure.Figured ignitial startup spun the bearing out of place.