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Discussion Starter #1
Purchased 67 SS Feb 2019 and got it almost road worthy. Car has GM 350. Based on engine casting 69 -79 year model, long tube headers, 700R Trans. Haven't been into motor but it cranks and runs well. Oil pressure is my concern. When engine is first started oil pressure 30-40 PSI. When warmed up, PSI stays about same running down the road. However when warmed up, PSI drops as RPMs drop. At idle (700/900 RPM) pressure drops to 8/11PSI.

With 500 miles on oil and filter change, oil still clean on dipstick and no oil loss. So, any ideas on getting PSI up? New oil pump? If so, recommendation on mfg brand? Is old logic 10 PSI per 1,000 RPM acceptable or old wives tale? Appreciate feedback.
 

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That's plenty of oil pressure, even at idle. If you want higher oil pressure you could use a higher viscosity oil. There won't be any more oil flow, but the pressure will be higher.
 

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I would think if the pressure was really that low your lifters would be making noise. Do the easy stuff first and replace the OP gauge sender.
 

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Discussion Starter #4
New digital OP sender and gauge (Dakota VHX). No noticeable engine noise. When oil was changed I used 10W40 Castrol. Appreciate the feedback.
 

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A lot of right answers here. The pressure you have is not a concern. Run 20/50 if it bothers you, as far as idle are you saying it idles 700 in drive and 900 in park? And finally throw a mechanical gauge in to check your low rpm readings. It SHOULD be accurate across the board but it could be off at lower readings.
 

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Discussion Starter #6
Yes, idle 700 in gear, 900 in park. Based on feedback, I'm going to watch, checking oil for cleanliness, level and consistency of PSI readings as I drive it some more. Checking with a mechanical guage for comparison is a good suggestion. Again, thanks to all.
 

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If it really bothers you it is possible to shim the spring or add a high volume/pressure oil pump. A good bit of work but really not that much money. I don't mean to be adding things for you to start worrying about but I have seen a few oil galley plugs work loose and they did make pressure drop. If you decide to change oil pumps I've always used mellings . The HV and standard oil pumps do take different pickups sometimes if using a aftermarket oil pan.
 

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i had the same with oil pressure on a 327 all last year. after the engine warmed an i came to a stop in gear i watched the pressure go down to 9 pounds but back up as soon as i speeded up to 28 pounds but had 33 when cold. it was a problem that just bothered me some would say 1000 rpm's an 10 pounds is good. so i had a quality speed shop look into it. they dropped the steering link then pan. the pick up tub was loose to the pump. so a new melling pump no high volume or high pressure, just an original style pump was installed. an at the same time a new fuel pump was installed, ac delco as a just in case. the fuel pump was very old. any way now i have 45 pounds at cold start up an running down the road at 32-35. at a stop in gear an warmed engine i'm at 22-24 pounds. also i did hook a different oil pressure gage in just to check before i had this job done, same reading. an this is in a 66. keep us posted as to what you finally end up doing.
 

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it was a problem that just bothered me (that) some would say 1000 rpm's an 10 pounds is good.
I worked at a local Chevy dealership for 10 years in the parts department. I heard the mechanics tell this to customers on many occasions. I think that 10 lb at 1,000 rpm is on the low side,
 

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onecarnut....thats what i thoght also 10 psi was on the VERY low side. but now it's at 22-24 i feel better an i think i heard my 327 say, "thank you "
 

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Discussion Starter #11
Got about 200 mile trip planned for Saturday. If all goes well thinking as I don't know anything about the motor I'll get it on the lift next week and pull oil pan to see what I can see. This is my initial post and viewing of site. As my fellow Mississippian would have said, "Thank Ya Thank Ya Very Much".
 

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Got about 200 mile trip planned for Saturday. If all goes well thinking as I don't know anything about the motor I'll get it on the lift next week and pull oil pan to see what I can see. This is my initial post and viewing of site. As my fellow Mississippian would have said, "Thank Ya Thank Ya Very Much".
Are you from Mississippi
 

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Is there a problem with your oil pressure? No, it will lubricate your engine just fine.
It does seem lower than is normal, but for an older engine with probably a stock pump, the pump may be getting worn but nowhere that "requires" that it be replaced. If your bearings/crank were so worn down to cause a loss of oil pressure with a 10w30, you would definitely hear some thumbidy thump.
If you do opt to replace your oil pump, a standard volume/pressure unit from Melling is all that's required. I think it's the model 55 is the std/std unit.
 

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Discussion Starter #15
Mississippian by God's Grace. Elvis's brother by another mother (and father). Musical talent, I play radio really good!
 

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Discussion Starter #16
Took trip Saturday 3/7. At 70 MPH, 2,000 RPM's, Temp gauge 160 degrees (weather mid 50's) oil pressure stayed steady at 38 PSI. Increase of RPM increased PSI. Return trip mid same speed, Temp 175/180 (weather upper 60's) PSI stayed steady at 32.

Idle at 700 RPM, PSI at 10. For now I'm just going to drive her and watch for any changes. As my friends in New Orleans would say, " Laissez les bons temps rouler". If you don't know cajun French, Let the Good Times Roll.
 

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thats great on the rpm's at 70 mph an 38 psi. i was told its the flow not so much as the lower pressure. you could kick that 700 rpm up to 900-950 an pick up a few pounds. enjoy the cruise.
 

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How many Novas came with an oil pressure gauge? Most just had an idiot light, and thousands of folks drove thousands of miles with no clue about the actual oil pressure, only that the light wasn't on.
 

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How many Novas came with an oil pressure gauge? Most just had an idiot light, and thousands of folks drove thousands of miles with no clue about the actual oil pressure, only that the light wasn't on.
Is that what that annoying red light was all those years???????
:ROFLMAO:
 

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makes you think, just what pressure did that light come on ? at zero or maybe 5 psi.
 
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