Oil pressure question… or two questions

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Doppleganger

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Heres a good explanation :)
I had a good friend who worked for Echlin back in the 70s, and through them, with Smokey Yunick, when Smokey was proving wrist pin position HP theories using 327's that my friend helped build.

Anyone referencing Smokey knows more than the books tell. :pimp:
 

Dooley

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The rule of thumb is 10lbs for each 1,000 rpm.
Words of wisdom right out of Eddie Lanier's mouth.
 

80BrownK10

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My oil pressure with a factory mechanical gauge reads 38-40 PSI cold at idle and 32-35 PSI warm. I run 10W30. I wouldn't let your pressures worry you, be thankful you have that much. I worry in the summer when the temp is over 100 about low oil pressure but it never goes below 30 PSI so I'm happy. I've got about 85,000 miles on the original engine in a '75 Scottsdale.
I know it's a mental thing but your oil temperature not that much different when it's 100f outside vs 85f. It's already several hundred degrees in a hot engine already
 

80BrownK10

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The rule of thumb is 10lbs for each 1,000 rpm.
Words of wisdom right out of Eddie Lanier's mouth.
Derek Bieri says that he learned from his dad and other dirt track racers said that the Chevy small block only needed 7-8psi per 1000. BUT those guys are trying to win races and are not trying to run those engines several hundred thousand miles.
 

Snoots

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It's always going to drop and vary after warming up. As long as you're using an oil that is suitable for your locales weather conditions and your driving habits you should have nothing to worry about. Then again, oil filters haven't been discussed and that IS a can of worms for another thread.
This can get really deep.
My '73 GMC has 496,000 miles on it and holds 35 lbs with a slight vary. I change the oil and filter every 3K miles. My '73 Firebird has 278,000 . . . same deal. My '88 Fiero (V6) has 465,000 same thing. My '64 Pontiac 326 had 298,000 when I sold it and it had 30-35psi oil prressure when I sold it (Iwas stupid).
I don't believe you should have a concern.
 

80BrownK10

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I change the oil in my k10 yearly. I use 15w40 with a quality filter. I usually put about 1000 miles a year or less on it.
 

AuroraGirl

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It's always going to drop and vary after warming up. As long as you're using an oil that is suitable for your locales weather conditions and your driving habits you should have nothing to worry about. Then again, oil filters haven't been discussed and that IS a can of worms for another thread.
This can get really deep.
My '73 GMC has 496,000 miles on it and holds 35 lbs with a slight vary. I change the oil and filter every 3K miles. My '73 Firebird has 278,000 . . . same deal. My '88 Fiero (V6) has 465,000 same thing. My '64 Pontiac 326 had 298,000 when I sold it and it had 30-35psi oil prressure when I sold it (Iwas stupid).
I don't believe you should have a concern.
is that fiero a 2.8 or whatever the stock engine was or is that a 3800 swap?
 

Rusty Nail

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No. But if you've still got the factory configuration, the amber "CHOKE" light in the lower part of the speedometer is actually an oil pressure warning light, and can grab your attention if oil pressure becomes critically low. It's connected to a second sending unit near the one for the oil pressure gauge, and its main purpose is to only send power to the electric choke heater once the engine is running... on the few trucks that didn't get the gauge package, the same idiot light sender was used to power the electric choke, but the warning light in the instrument cluster was red, and was labeled "OIL/CHOKE" (and was moved to the spot occupied by your oil pressure gauge).

Your oil pressure sounds pretty normal to me. I usually see 35-45psi on a cold start, and it stays somewhere in there until the oil temperature comes up... and this is usually a number of miles after water temperature stabilizes. Once oil is up to operating temperature, it's about 30-35 at speed, and around 20 at idle. After a long run on the freeway, it can hover around 15 at idle and 30 at speed.

My oil pressure gauge sender is getting ready to sh¡t the bed, and occasionally reads zero on cold starts... but since the "CHOKE" light goes out, I know I've got oil pressure.
This is a good post.
 

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