Oil pressure question?? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

smoked68 · 12-16-2008, 07:43 PM

SB 4 bolt 350, how much oil pressure should I be running at idle, which I have at 900 rpm and how much say at 3400 rpm's which is about 65 mph? I am thinking my oil pump is not pumping as it should. I'm running 10/40 Valvoline. It will pump up real slow to about 35 lbs then as the oil heats it drops. Just curious what is normal. At temp it will Idle at about 15 to 20, at speed about 25 lbs. Normally operates at about 185 deg. I have an Autometer OP gage. Thanks, Mike

t&tkennels · 12-16-2008, 07:50 PM

ive always heard 10lbs per 1,000 rpm.

bigguy69 · 12-16-2008, 07:54 PM

mine holds about 80 lbs at idle when you first start. about 35 lbs after it warms up 190. just rebuilt with a high volume oil pump. but it will go up to about 60 lbs at speed

smoked68 · 12-16-2008, 08:57 PM

I had heard the 10 lbs per 1000 before but what would be the max? Also what type hi vol would I go to. I know too much is as bad as too little.

Gray Ghost · 12-16-2008, 11:58 PM

You are in the range of most oil pumps. Ideally you want 15 lbs at idle and 30-45 at highway speed depending on the age of your motor.

smoked68 · 12-17-2008, 12:09 AM

Thanks, I was getting worried. My get a higher prss. pump anyway though. Any suggestions of who what where, I know the when...preesh...

Gray Ghost · 12-17-2008, 12:15 AM

Mine's a Melling and it's a high volume versus a high pressure. I was told the high pressure can blow out normal seals fairly easily.

**WorkinLonghorn** · 12-17-2008, 12:19 AM

The original "Truck Data Book" from 1969 says for 350 engine " Normal Pressure (psi); 30@ 1170-2000 rpm".

Huck · 12-17-2008, 09:58 AM

10-15 at idle is fine and 40-80 at running speed is also fine. I personally would only use Valvoline Oil for lube on bicycle's. Most of the Pa oils contain trace amounts of parafin (wax) and will build up over time to form a thick waxy base on the head etc. Most shops and racers like high detergent oils that keep things clean like Castrol. I've run it in everything from $70K porsch's, vets, bmw's with never a build up or oil failure. My .02

12-16-2008, 07:43 PM	#1
smoked68 Registered User Join Date: Oct 2006 Location: Rock Hill, SC Posts: 421	Oil pressure question?? SB 4 bolt 350, how much oil pressure should I be running at idle, which I have at 900 rpm and how much say at 3400 rpm's which is about 65 mph? I am thinking my oil pump is not pumping as it should. I'm running 10/40 Valvoline. It will pump up real slow to about 35 lbs then as the oil heats it drops. Just curious what is normal. At temp it will Idle at about 15 to 20, at speed about 25 lbs. Normally operates at about 185 deg. I have an Autometer OP gage. Thanks, Mike __________________ 1968 chevy shortbed, Dark Shadow Gray 4 bolt 383 Stroker,Weiand Super Charger, disc brakes, 9 inch, 391 gear, 20" Eagle wheels, muncie 4 speed/ Hurst shifter, 4/7 drop, Hedman midlengths, 3 inch exhaust w/ 2 chamber flows. 1966 Mustang with 306 roller, c-4, 9 inch Detroit locker rear. 1965 Fastback Mustang w/347 stroker, top loader 4spd, 9 inch detroit locker. 1966 Mustang coup, 306 roller, c4, 9 inch. 65 Cobra, 427, T6oo, 9inch, of course. First gen Hayabusa, airbox mod and running 2 exhaust cams.. Zoom Zoom Zoom

12-16-2008, 07:50 PM	#2
t&tkennels Registered User Join Date: Sep 2007 Location: creedmoor n.c. Posts: 188	Re: Oil pressure question?? ive always heard 10lbs per 1,000 rpm.

12-16-2008, 07:54 PM	#3
bigguy69 dazed and confused Join Date: Jul 2008 Location: marion nc Posts: 1,649	Re: Oil pressure question?? mine holds about 80 lbs at idle when you first start. about 35 lbs after it warms up 190. just rebuilt with a high volume oil pump. but it will go up to about 60 lbs at speed Last edited by bigguy69; 12-16-2008 at 07:57 PM.

12-16-2008, 08:57 PM	#4
smoked68 Registered User Join Date: Oct 2006 Location: Rock Hill, SC Posts: 421	Re: Oil pressure question?? I had heard the 10 lbs per 1000 before but what would be the max? Also what type hi vol would I go to. I know too much is as bad as too little. __________________ 1968 chevy shortbed, Dark Shadow Gray 4 bolt 383 Stroker,Weiand Super Charger, disc brakes, 9 inch, 391 gear, 20" Eagle wheels, muncie 4 speed/ Hurst shifter, 4/7 drop, Hedman midlengths, 3 inch exhaust w/ 2 chamber flows. 1966 Mustang with 306 roller, c-4, 9 inch Detroit locker rear. 1965 Fastback Mustang w/347 stroker, top loader 4spd, 9 inch detroit locker. 1966 Mustang coup, 306 roller, c4, 9 inch. 65 Cobra, 427, T6oo, 9inch, of course. First gen Hayabusa, airbox mod and running 2 exhaust cams.. Zoom Zoom Zoom

12-16-2008, 11:58 PM	#5
Gray Ghost Senior Member Join Date: Sep 2004 Location: Terrell, TX Posts: 1,967	Re: Oil pressure question?? You are in the range of most oil pumps. Ideally you want 15 lbs at idle and 30-45 at highway speed depending on the age of your motor. __________________ Kelly '05 GMC Sierra SLE Z71 Bone stock except for new bed rail caps.

12-17-2008, 12:09 AM	#6
smoked68 Registered User Join Date: Oct 2006 Location: Rock Hill, SC Posts: 421	Re: Oil pressure question?? Thanks, I was getting worried. My get a higher prss. pump anyway though. Any suggestions of who what where, I know the when...preesh... __________________ 1968 chevy shortbed, Dark Shadow Gray 4 bolt 383 Stroker,Weiand Super Charger, disc brakes, 9 inch, 391 gear, 20" Eagle wheels, muncie 4 speed/ Hurst shifter, 4/7 drop, Hedman midlengths, 3 inch exhaust w/ 2 chamber flows. 1966 Mustang with 306 roller, c-4, 9 inch Detroit locker rear. 1965 Fastback Mustang w/347 stroker, top loader 4spd, 9 inch detroit locker. 1966 Mustang coup, 306 roller, c4, 9 inch. 65 Cobra, 427, T6oo, 9inch, of course. First gen Hayabusa, airbox mod and running 2 exhaust cams.. Zoom Zoom Zoom

12-17-2008, 12:15 AM	#7
Gray Ghost Senior Member Join Date: Sep 2004 Location: Terrell, TX Posts: 1,967	Re: Oil pressure question?? Mine's a Melling and it's a high volume versus a high pressure. I was told the high pressure can blow out normal seals fairly easily. __________________ Kelly '05 GMC Sierra SLE Z71 Bone stock except for new bed rail caps.

12-17-2008, 12:19 AM	#8
WorkinLonghorn Senior Member Join Date: Dec 2006 Location: Studio City, Calif. Posts: 2,861	Re: Oil pressure question?? The original "Truck Data Book" from 1969 says for 350 engine " Normal Pressure (psi); 30@ 1170-2000 rpm". __________________ '69 GMC C2500 Custom Camper, 8 1/2' bed, New GM 350, NP 435 Close Ratio 4spd. Trans., 3.73 Dana-60 open.Camper and Trailer wiring, PS, PB, AC, tach , three gas tanks, 2nd owner, Work-Truck supreme. Best $300 I ever spent.

12-17-2008, 09:58 AM	#9
Huck Senior Member Join Date: Jun 2001 Location: Shelbyville, KY Posts: 3,269	Re: Oil pressure question?? 10-15 at idle is fine and 40-80 at running speed is also fine. I personally would only use Valvoline Oil for lube on bicycle's. Most of the Pa oils contain trace amounts of parafin (wax) and will build up over time to form a thick waxy base on the head etc. Most shops and racers like high detergent oils that keep things clean like Castrol. I've run it in everything from $70K porsch's, vets, bmw's with never a build up or oil failure. My .02



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