I have a 383 stroker in my 67 Chevelle. The engine has supposedly 2500 miles on it.

The issue is the oil pressure readings. When starting at cold, the pressure is up around 40 plus. At warmup if I am driving it the 40 to 60 range, the oil pressure is in the 30 to 35 range, usually staying around 32.

However, at idle the oil pressure is around
10 to 12 psi. Sometimes it drops to 8 psi.
When accelerating again from idle the oil pressure goes up in increments, based on speed, to 30 to 32 psi.

My concern is the idle pressure. Is this oil
pressure at idle too low and should it be higher ?

I have had conflicting opinions and see addtional advice.

There is no blue smoke or knocking that I can detect at this time.

Thanks,

Ken McDee

My understanding is that you need 10 psi of oil pressure for every 1000 rpm of engine speed. If you have atleast this, you should be ok.

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aka Scott B.
1967 Malibu
406 cid / 350 TH
Under Constuction

My 350 has the same issue- 10-12lbs at hot idle- 35-40lbs at rpm.

When I bought the car last spring I about came unglued, because I didn't notice until after I had driven it a few times and let it get all the way warm that the pressure went down so low... This engine was a Recon remanufactured engine..

I had people giving me opinions ranging the from the engine is toast no way should it be that low- to that is just fine...

I've run the thing 8k miles this year- no problems at all... I've come to the conclusion that its just fine- as long as it goes up with the RPMS & doesn't go much be low 8lbs or so...

Just run it! If there is no knocking, and the pressure readings at idle & rpm stay consistant over time then you are probably just fine.



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Ben Rambow
1970 El Camino SS (http://www.elcaminoclassics.com/code/rambow1.htm)
My old 1969 El Camino (http://www.chevelles.com/feature/july2001.html)
The El Camino Classics Club (http://www.elcaminoclassics.com)
"Whats the matter with the car I'm Driving? Can't ya tell that its out of style..."

Have you tried another guage to make sure yours is reading correctly? It could be a guage problem and nothing to do with oil pressure.

With only 2500 miles on a fresh engine i would think it should be higher. Around 25-30 at idle and climb from their.
For instance i put together a 355 for a pickup and before the rebuild it would run areound 10-15 at hot idle and MAYBE hit 35 on the road. The bearings were wore bad and after new bearings and getting clearances in check, it runs around 25 at hot idle but climbs immedialty and pegs the gauge when you get on the gas.

My 454 idles around 10-15 p.s.i. hot, and climbs 10 p.s.i. per 1000 RPM. Does seem low, but I guess it's just fine from what I've read from some of the other guys on here. http://www.chevelles.com/forum/smile.gif

[This message has been edited by 70_Malibu (edited 01-07-2003).]

One car manufacturer I worked for in the 70's allowed idle oil pressure to go to 4psi before lighting the idiot light. No problems with that so far as I know.

my 454 runs 40+ all the time

Your oil pressure is too high at idle. You should only have 8lbs at idle like everyone else. http://www.chevelles.com/forum/biggrin.gif I built a 400 small block for my dad 86 Monte Carlo SS and it runs about 10-15 lbs at idle. I have no idea why but it goes up when the throttle is hit.

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69 Malibu 406 3680lbs Turbo 350 2400 stall, 3.73,XE274, Performer RPM Q-JET, 800 Q-JET, Sportsman2 64cc 11TO1 12.65@105.5 mph on Drag Radials

ACES Member #3635
Tri-State Chevelle Member# TSC-010
Larry G.

you need too look at mine 65 at idle and beyond belief at warp speed ...but iam talking about a stock bore & the stock pistons 10/10 polised & caifed crank and 305 small valve sodeum filed truck heads with 2brl intake & rodchester carb. high valum oil pump with a 1/4 in washer on top of spring. and yes it can kill a oil filter.and i run it every weeked at the dirttrack every chance i get and it going on it 3rd season

My 383 was "balanced and blueprinted".
Not even sure if that applies to a 383.

It was also race prepped.

I used a Moroso blueprinted oil pump.

Fresh engine, with new Pensoil 10w-40:

Idle cold: 70psi

Idle hot: 10psi (probably is close to 1000rpm)

Crusing cold: 70psi.
Crusing hot: 35-40psi.

I had hoped for higher pressures at idle too, but since a lot of these engines run forever with pressures like that, I won't worry about it.

Dave