383 Oil Pressure Too High

[lux]

My new built 383 oil pressure is high.
Idle pressure is 65psi @ 1000 rpm after warm up
5000 rpm is 95 psi.
Milage on the engine is 1100
The oil I’m running is VR1 20w 50
7 Quart oil pan, but I’m using 6.5 Quarts
oil filter is Fram HP4

I think the problem is the pump
I put in a Melodon 18756 , Standard Volume , High Pressure pump. I thought it was a standard pressure pump.

Do I have a problem?
Do I need to change to a standard pressure oil pump spring?
I seem to have a lot of small oil leaks.

[AussieinNC]

Originally Posted by lux

My new built 383 oil pressure is high.
Idle pressure is 65psi @ 1000 rpm after warm up
5000 rpm is 95 psi.
Milage on the engine is 1100
The oil I’m running is VR1 20w 50
7 Quart oil pan, but I’m using 6.5 Quarts
oil filter is Fram HP4

I think the problem is the pump
I put in a Melodon 18756 , Standard Volume , High Pressure pump. I thought it was a standard pressure pump.

Do I have a problem?
Do I need to change to a standard pressure oil pump spring?
I seem to have a lot of small oil leaks.

Why the VR1 oil? Is this a race engine? Is it roller cammed?

I would be looking at checking the accuracy of the oil pressure gauge first....

Then look at running a good quality 10W 30 oil instead with a supplement if the engine uses a falt tappet cam...

Then check pressures....

Both will not require removal of the pump.

If the pressure remains too high then look at replacing the spring in the pump.

Let us know how you go...

[lux]

Roller cam, roller rockers, aluminum heads, 10.4:1 compression. The 20w 50 was suggested by the engine designer. I reached out to them with questions but, their customer service is terrible.
I did put a standard gauge on it to check against the electric one. They both read the same.

[MySons68C20]

I have a similar build as well. The oil specs the same VR-1 20w-50 etc.
I'm seeing 50 lbs at hot idle (900 ish rpms) and 80 lbs at 5000.
I can't find the 10w-30 VR-1 locally but you can order online.
The next oil change I'm going that route.....

[lux]

Originally Posted by MySons68C20

I have a similar build as well. The oil specs the same VR-1 20w-50 etc.
I'm seeing 50 lbs at hot idle (900 ish rpms) and 80 lbs at 5000.
I can't find the 10w-30 VR-1 locally but you can order online.
The next oil change I'm going that route.....

Do you see small oil leaks?
I have one I can't find. I did get better valve cover gaskets to stop those from leaking. But, I'm sure those weren't because of high pressure.

[lux]

Mostly I'm wondering if I could be hurting the engine with oil pressure that high?

[Greasey Harley]

Originally Posted by lux

My new built 383 oil pressure is high.
Idle pressure is 65psi @ 1000 rpm after warm up
5000 rpm is 95 psi.
Milage on the engine is 1100
The oil I’m running is VR1 20w 50
7 Quart oil pan, but I’m using 6.5 Quarts
oil filter is Fram HP4

I think the problem is the pump
I put in a Melodon 18756 , Standard Volume , High Pressure pump. I thought it was a standard pressure pump.

Do I have a problem?
Do I need to change to a standard pressure oil pump spring?
I seem to have a lot of small oil leaks.

Why are you using 20/50? that is really thick oil for a sbc. 20/50 puts its share of wear on the oil pump drive/cam gear.
Personally I prefer High volume, standard pressure pumps I don't like high pressure pumps.
That being said, lots of high pressure pumps have lived long happy lives inside small block Chevy engines.
No small block Chevy ever lived a long happy life with a Fram oil filter atached to it. FRAM = JUNK

That's my $.02
-Russ

[gmc684x4]

Most gm factory roller cam engines are 5w30
20w50 is a diseil truck oil viscosity
I would change oil to 10w30 or 5w30 check oil pressure again and check that your guage is working correctly

[lux]

Yes, The 20w50 is a recomendation from the engine designer, Skip White Performance. I've tried to contact them many times for help but they don't reply.
Should I switch to 10w30 first, or change the oil pressure spring first? Or both?
Also I was under the impression that a Fram HP4 was a good filter for a high proformance engine,, please give me any better suggestion.

[MySons68C20]

I'm going to the 10W-30 anyways because this is not a race truck.
I prefer the Wix oil filter....never been a fan of Fram after seeing how they were made based upon cutaway pics from years ago.
Do the lighter weight oil first. Let the engine get to full temp after driving a bit and recheck pressure.

[kwmech]

I'd switch to the 10/30, but that isn't going to solve your pressure problem when the engine is at operating temp. You're still going to see in excess of 80 lbs. Change the pump

[lux]

I have the normal pressure (green) spring for the oil pump but, I think I'll change to 10w30 first. That way I'll have a gauge on what that does to the pressure for reference.

[MySons68C20]

That is exactly what I would do. Interested in hearing what the difference will be.

[sweetk30]

WIX filter gold / 10-30 or 5-30 oil run it .

if still not happy swap spring out .

https://penngrade1.com/history/ i know a lot of race car guys run this brand of oil . use to be called brad penn . . . its made from PA crude oil stock . https://penngrade1.com/products/high...il-sae-10w-30/

[garyd1961]

My L31-R crate motor pegs my factory gauge when cold and idles at the half way mark when hot. Cruising at 60 It's past the 3/4 mark hot. I have had another gauge hooked up before and the factory gauge is accurate. I'm running 10W-30.

[tdangle]

Originally Posted by garyd1961

My L31-R crate motor pegs my factory gauge when cold and idles at the half way mark when hot. Cruising at 60 It's past the 3/4 mark hot. I have had another gauge hooked up before and the factory gauge is accurate. I'm running 10W-30.

Mine is exactly the same. Factory gauge, L31 based SP350/357 GM Performance crate motor

[68 P.O.S.]

Originally Posted by lux

Yes, The 20w50 is a recomendation from the engine designer, Skip White Performance

That's your problem right there

[lux]

Originally Posted by 68 P.O.S.

That's your problem right there

Please elaborate?

[MySons68C20]

[QUOTE=lux;8902287]Please elaborate?[/QUOTE

I think 68 P.O.S. means that Skip White is not a top tier engine builder or supplier of quality parts. I personally have never bought anything from them just going by what others have stated.
I bought my crate engine from United Racing which is now out of business so no clue what they actually installed in my engine.

[GASoline71]

Skip White "performance" started life as just an ebay store that sold offshore junk parts (like $49 dollar HEI's). Now they are all of a sudden "Performance experts".

Gary

[lux]

I can tell you for sure that Skip White customer service is horrible. I wrote the same email for help to everyone listed in their company and none replied.

[Richard2112]

Oil viscosity for your engine is determined by the tolerances at your main and rod bearings and also upon the smoothness of the finish of each. A polished finish can work well with tighter tolerances and a thinner oil will develop a good hydrodynamic wedge for the journals to ride on. As your tolerances get looser and the finish a bit more rough a heavier weight oil is necessary. A general rule of thumb for engine building is to allow .001 clearance for each inch diameter of journal.

[Tom]

If your buying an engine and not building it, then chances are pretty good you don't know the clearences it was built with. Run the oil they recommend and change the pump to the correct pump for what you want. Kinda silly to install a high pressure pump, complain about the high pressure, and changes specs on the engine instead of fixing the initial problem.

[lux]

Originally Posted by Tom

If your buying an engine and not building it, then chances are pretty good you don't know the clearences it was built with. Run the oil they recommend and change the pump to the correct pump for what you want. Kinda silly to install a high pressure pump, complain about the high pressure, and changes specs on the engine instead of fixing the initial problem.

I did build the engine, I did measure all clearances. The high pressure oil pump was not intended. I ordered the correct one and recieved and installed the wrong one without checking the part number.
I ordered all the parts from Skip White, so it's their design. I just did not have enough money for them to build it. Plus I wanted the experience of building it myself.

[Richard2112]

Originally Posted by lux

I did build the engine, I did measure all clearances. The high pressure oil pump was not intended. I ordered the correct one and recieved and installed the wrong one without checking the part number.
I ordered all the parts from Skip White, so it's their design. I just did not have enough money for them to build it. Plus I wanted the experience of building it myself.

When I built my 383 I measured absolutely everything and I do mean everything. If it wasnt in my spec range I had it machined into my spec range. Had I written it down as I proceeded I'd have blueprinted by build. My rotating assembly was also balanced. But at each step of the build I was looking for tolerances that gave me assurance that I could run 10w30 oil. I don't recall now what those specs were (I measure for a great many other reasons also) but I do know that my clearances allow for 10w30. If your clearances are greater than the .001 per inch of journal diameter then a heavier oil may be warranted depending upon how much beyond that tolerance the clearances are. I use a standard pressure pump on my build and it does fine.