allright it's a 84 TA with a swapped 350. It holds about 40 at idle for awhile then it'll drop to about 10 or 12. When you drive her down the road she'll achieve between 40 or 50. But the 10 or 12 at idle alarms me and it sometimes drops to 20 or 30 while driving also. Is this a problem and if so what's the fix cause i'm not for sure. It holds up pretty good and only leaks about quarter size puddle a night.

 

that doesnt sound right...

my engine idles at 50psi...
but the dropping down to 10-12 doesnt sound good....

 

i figured that isn't healthy but could it be the gauge although it's aftermarket. Where could i be losing pressure at?

 

yeah, it could be the gauge... is it a tube thing or a wire???

i had an oil pressure gauge fail, it would work and then it would drop to nothing... scared the crap out of me, so i pulled over checked everything out, ended up driving the half mile home slowly... (probably not a good idea if the oil pressure was gone... anyway, took the gauge cluster cover thing off, tapped the gauge and it went back up again, so i replaced it and hasnt messe dup since...

you might try that... when it drops way down, tap on the gauge or soemthing...

 

hey it's a tube and i'm goin to check the other end of it when it gets out of the shop.......i hate transmissions.

 

10 Psi for every 1000 rpm. If my car is very hot, ill go down to 20 at idle, but 90% of the time its 30psi at idle.

 

Mines about 40 at idle warm, and about 50-55 driving.

 

when you swapped the motor....did you put in a fresh oil pump?

I consider that a must. And I choose the hi-volume pump with steel sleeve to the OP driveshaft...its your engines blood. Don't ever cut corners.

 

10 psi per 1000 rpm, screw a mechanical gauge in the engine somewhere to see what you really have. i'd never run a HV pump except on an engine that lives at or above 7000 rpm and only then with a extra capacity pan to supply it.

 

I have a 3.1 v6 and at idle mine is around 60psi what gives??? The pressure has been high like that for the past 3 years. the enigne has 222,XXX miles on it. Is it a sign of a problem

 

this is just the question I wanted to ask so rather than make a new post I'll just ask here.

I got a mechanical gauge in, and it's been a few days since I switched back to M1 15-50(wanted to make sure readings were consistant) at cold start up, idle in park(850rpm) and drive(650rpm) my oil pressure is 35psi, if reved a little it goes up to 40psi. once the car gets to opperating temp(between 160* & 220* on the gauge) wile ideling in park oil pressure is 30psi, idle in drive is 20psi. when driving oil pressure is always between 35-30psi depending on engine temp(when regular driving, aside from getting off a stop light/sign engine speed is always below 1700rpm). pressure will increase to 40psi if I realy get on the gass at a stop light/sign, but I never go above 4000rpm.

are these pressure readings ok for an LO3?

 

dragon your oil preasure is fine and normal.

 

hey guys


i think that is normal oil pressure for a high mileage lo3. My car at startup will acheive 50 psi cold.When it gets hot it drops to around 30 and if i have been driving like a mad man it will drop just below 30 possibly 20. It has been like that for over 20k and i run the hell out of it 155k on the clock. Also guys the owner's manual tells ya with a filter change the motor hold 5 qts, wrong mine show over full ever with the pf 35 ac truck filter. check it sometime.I think the lo3 is a 4.5 qt pan cause when i use the larger filter it takes 4.75 qts to fill her up. cause if it is overfilled you could be airating the oil cause a major drop in oil pressure.


i had a buick 3.8 that wouldn't hold 10 psi at idle hot run the **** out of it. Then i killed the motor by knock! 20 psi of boost with a fuel pump going lean makes for bad things. RIP

 

thanx for the reply ede and SC2camaro. I couldnt find the chart in my chiltons manual that said what the oil pressure should be, and I realy wanted to make sure it was doing ok.

and I def say my LO3 is high milage. its getting near 200,000 miles and from what I can tell it had a hard life b4 I got it. so I guess its doing rather well. she runs alot better now(if you heard the car when I got it in jan, then heard it now youd swear it was two diffrent cars) and its thanx to you all here on the baord that have helped me when I needed info :hail: