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Topic: Oil Pressure

Oil Pressure (1/3)
 6/14/19 8:29pm
Dblancha79Gold Member
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Weatogue, CT - USA

Vette(s):
1979 C3 L82 383 cu in


Joined: 6/29/2015
Posts: 49

My oil pressure runs 80 PSI over 2,000 rpm and 45 psi at idle or 700 rpm. Is this typical for a C3 79' L82?  I was told today that 45 psi  to 20 psi is the norm for standard oil pump and stock oil pan for this 350  small block.  He said I may be pumping my stock oil pan dry at the higher rpm's causing the engine oil and engine to overheat.



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"Made to be run hard"
Simsbury, Ct.

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Re: Oil Pressure (2/3)
 6/14/19 10:16pm
Adams' AppleLifetime Member
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Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas


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80psi of oil pressure will not pump the pan dry, by any means....PSI is a measure of pressure, not volume. A high volume pump can suck a pan dry in certain instances, but not a high pressure pump. Are you getting your pressure readings for the factory, electrical gauge, or do you have a quality mechanical gauge?

80 psi(hot) at road speed is a bit much, I would agree. Chances are someone possibly installed a high pressure pump somewhere down the road. Can't say that I would agree with that causing an overheating issue in normal driving conditions. My '74 will hit 75-80psi on a cold start, and then settle down to 45psi at idle once warmed. Never seen it go below 45 psi ever, no matter what rpm. Basic "Rule of thumb" for oil pressure required is 10 psi for every 1000 rpm. 

Oil viscosity might have something to do with the high pressure, also...what oil are you using?



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Re: Oil Pressure (3/3)
 6/15/19 7:00pm
Dblancha79Gold Member
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Weatogue, CT - USA

Vette(s):
1979 C3 L82 383 cu in


Joined: 6/29/2015
Posts: 49

I hooked up a pressure gauge to the motor and validated what the electric gauge was stating.  I burned up the main bearings time trialing the car and just replaced them. This car has always overheated despite my aluminum 3 row radiator, 160 degree thermostat and validating all the sensors were working properly.  I think something else and not the  the coolant is causing the engine to overheat.  I just switched to 10w30 full synthetic oil vs the 10w30 standard oil I was using after I installed the new bearings. I have ordered dual electric fans and after I get them installed I will have to see where I'm at.

thanks for advise.



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"Made to be run hard"
Simsbury, Ct.

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