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Oil Pressure, Too Much??

I think you are good. Every engine is different depending on the tolerances. I have one Hemi that is 85-90 cold and 60-70 warmed up and no lower than 50 idling at 185 degrees. No problems with 10K miles on the build.

Same here ,440 SIX PACK , Built 12 years ago ,2500 miles, 90 cold and 65 / 70 hot. 10W30 HP Royal Purple , Tim @ forhemisonly build said it would be fine & it is ! 190 degrees
 
When we were young we used 20w50 Kendall GT-1. It was racin' oil man! our engines in our used Mopars needed it! If 10w30 was good, 20w50 was better. What did we know.
 
When we were young we used 20w50 Kendall GT-1. It was racin' oil man! our engines in our used Mopars needed it! If 10w30 was good, 20w50 was better. What did we know.

Any yet, they survived.

We love to talk oil to death. But the reality is, go buy the cheapest motor oil you can find, at any W rating, and your <600 hp motor will be 100% happy as long as you always have adequate oil pressure.
 
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Running a stock 78 400 4bbl motor with 57k miles. Everything looks perfect inside. Just got it fired up the other day for the first time since getting it. Wix filter and 20 w50 (didn't realize it wasn't 10w 40 until I was home) VR1 oil. Cold she hit 80lbs, once she hot between 40 and 50. Is that too high of pressure? change to 10w 40 or is the 20w 50 ok for now? Thanks!

Are you running a standard Wix filter or a Race Wix filter ? BIG difference.
 
Referring to my earlier post on why I swapped over to a lower vis racing oil, here are a couple of excerpts here from a 50 page study on motor oils:
…many folks believe that oil pressure = lubrication, but that is simply NOT the case. Pressure is only a measurement of resistance to flow. But, oil FLOW is lubrication, and you get more flow with thinner oil as we just saw above. Lubrication is what is used to separate moving parts, and keep them from making metal to metal contact, which results in wear/damage. And increased flow also has another very important advantage. An engine’s vital internal components are all DIRECTLY OIL COOLED, but only INDIRECTLY water cooled. And thinner oil will flow more freely, carrying away more heat, thus providing better cooling for those vital internal components. And of course that extra cooling is even more important in high performance engines. So, going to the trouble of achieving almost an extra 20% in flow, is well worth the effort. If someone asks why use a high volume pump, the answer is so that you can maintain reasonable oil pressure with thinner oil. And with thinner oil, you can improve both lubrication and cooling. Reduction of 5 to 10 HP can be caused by higher-vis oils.
Here are some comparison numbers from an 830 HP road race engine, on the track:

15W50 oil = 80 psi = 265* oil temp............5W20 oil = 65 psi = 240* oil temp

The thicker oil flowed more slowly through the bearings, thus getting hotter and driving up bearing temps. If an engine is running hot, use a thinner oil to increase flow and increase cooling. And running a high volume oil pump allows you to do that. ...the “Ideal Lubrication Setup” for most traditional engines, is a high volume/high pressure oil pump with a thinner multi-viscosity motor oil

Thicker oil does not automatically provide better wear protection than thinner oils. Extensive “dynamic wear testing under load” of dozens and dozens of motor oils, has shown that the base oil and its additive package “as a whole”, is what determines an oil’s wear protection capability, NOT its viscosity. So, don't run thicker oil under the false assumption that it can provide better wear protection for our engines.

•BOTTOM LINE: Thinner oils are better for most engine lubrication needs.


Notable source of wear is due to cold start up and my ride can sit for a couple weeks without running it and longer in the winter despite being in a heated garage. Seems that faster flowing oil is a better thing.
Exactly - I agree 100%!

Oil flow (obviously with some reasonable pressure) is what an engine needs. Go to excess with either one and you are hindering, rather than helping, the engine.
 
I'm convinced. Ill just make sure I grab the 10w 40 next time and watch what the gauge does
 
Amsoil 10-40.
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This is a rod bearing from a 15-1 572 running to 7200 rpm. 5w25 oil running a Wix 515R race filter. 476 passes. See any dirt scratches?
Doug

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You guys got me wondering if I have to much pressure on my 493 stroker. Has 5 - 600 miles on it. 80 pounds cold, 70 pounds going down the road at 2800 rpm, and 25 pounds hot at idle. Brad Penn 10w-30.

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Perfect - Same exact numbers as my 432 Stroker in my 71 Bee - Valvoline VR1 and WIX Filter

I can honestly say i didnt really notice any difference in oil pressure when hot , between 10W 30 and 20W 50 VR1

Full groove main bearings
 
So this was an interesting test:
I heated some 10-30 and some 20-50 to 220°.
I then filled two squirtguns with each oil to see which one would squirt the farthest, and to feel the difference in trigger effort.
The internal feed tubing melted on both and the whole thing was a failure.
 
Running a stock 78 400 4bbl motor with 57k miles. Everything looks perfect inside. Just got it fired up the other day for the first time since getting it. Wix filter and 20 w50 (didn't realize it wasn't 10w 40 until I was home) VR1 oil. Cold she hit 80lbs, once she hot between 40 and 50. Is that too high of pressure? change to 10w 40 or is the 20w 50 ok for now? Thanks!

I'll take some of your oil pressure. Right now my 400 has zero oil pressure. Reason unknown at the moment. I know from my casting number my 400 is from a 76-78 car. It's in my 74 SE that was factory 400. How can I pin down more info on this motor? I would love to know the exact year and perhaps what car it came out of. Thanks!
 
So this was an interesting test:
I heated some 10-30 and some 20-50 to 220°.
I then filled two squirtguns with each oil to see which one would squirt the farthest, and to feel the difference in trigger effort.
The internal feed tubing melted on both and the whole thing was a failure.
Good thing ya didn't burn your hands. Years ago a friend's direct oil line to the gauge burst in his ride and he got some nasty burns on his leg and a hell of a mess in the car. Ever since I've used electric..
 
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