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Excessive oil pressure
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Re: Excessive oil pressure
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Re: Excessive oil pressure
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Re: Excessive oil pressure
Gnicholson you posted about balance grooves, could tell us more? Would that make a difference in the pressure also. If I would remove the lump and put a lighter spring in should I make this modification?
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Re: Excessive oil pressure
When would a HV oil pump be required or recommended? Piston squirters? Oil spring cooling? I guess at that level you'd be drysumped.
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Re: Excessive oil pressure
im talking about grooves machined or cut into the pump body and cover. the idea is to dampen pump pulses that cause spark scatter etc. it also creates internal leakage and lowers idle oil pressure some. this mod has been around a long time and moroso makes pumps that allready have this done. obviously you have to remove the pump to do this and if you do that you might as well just put the z28 pump in. im not sure what lump youre talking about. how much oil pressure does it have now hot at higher engine speed?
Re: Excessive oil pressure
Several interesting reveals in the data Kevin posted:
0 Huge difference in the pressure pulsation between a coarse tooth gear type and and a fine tooth crescent type. Wonder what a 12 tooth gear output would look like?
o Big difference the opposite way re power absorption, but all suck up far less than many people think/claim: At only 2 HP @ 6,000, no magic is going to give a significant reduction, especially if the curves are pump RPM vs. engine speed, e.g. crank-driven LS vs cam driven SBC.
0 Huge difference in the pressure pulsation between a coarse tooth gear type and and a fine tooth crescent type. Wonder what a 12 tooth gear output would look like?
o Big difference the opposite way re power absorption, but all suck up far less than many people think/claim: At only 2 HP @ 6,000, no magic is going to give a significant reduction, especially if the curves are pump RPM vs. engine speed, e.g. crank-driven LS vs cam driven SBC.
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Re: Excessive oil pressure
Melling also makes anti cav pumps for both the sb and bb.
Those ones have a C at the end of the part number.
Guy
Those ones have a C at the end of the part number.
Guy
'86 Monte SS,513 BBC,AFR heads,Bullet solid roller cam,Doug Nash 4+1 5 speed,Hurst Inline Shifter,Ford 9 inch Rearend.
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Re: Excessive oil pressure
Melling also offers a pump with helical gears for smoother oil flow and drive loads [which was their target], looking at the twist in their video they didn't go far enough from my experience to make much difference. And to answer the repeated question " Why High Volume" pumps are used, they were built for "Loose" engines, [band-aid a worn engine, or for an engine built looking to reduce parasitic loses from a tight bottom end] and potentially other things like twin turbo's, bypass coolers and some of the other stated things from etc.. Harry P.S. Here is Melling's YT vid:https://www.youtube.com/watch?v=KGxt2i96QEs
Re: Excessive oil pressure
I guess that I would have added some good old MMO on top of my oil and then checked my oil pressure before I would have went to too much trouble trying to lower it. Maybe up to a cup of MMO...
And back when I was a kid, I ran 10 wt in the winter and 30 or 40 wt in the summer, straight blend. He, He!! The bulk stuff in the quart canning jars with the metal pour spouts that set out front by the pumps...
pdq67
And back when I was a kid, I ran 10 wt in the winter and 30 or 40 wt in the summer, straight blend. He, He!! The bulk stuff in the quart canning jars with the metal pour spouts that set out front by the pumps...
pdq67
Re: Excessive oil pressure
I didn’t know horse carriages used oil...
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Re: Excessive oil pressure
Ok hear goes. I changed oil from 15w40 to 10w30 Valvoline VR1 today. Cold idle is #65 after driving for 30 minutes idle at the stoplight down to #35-40 & 60 at cruise. Engine runs awsome.
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Re: Excessive oil pressure
Wilson1970...an engine with average clearances will be just fine with 10-30 wt. Hard to beat with ambient temps between 50 to 100 degrees . My personal opinion. Mark H.
Re: Excessive oil pressure
That is a standard volume pump with a 3/4" inlet pictured, and that is what GM used from about 96 on.Kevin Johnson wrote: ↑Sat Sep 22, 2018 12:48 pmAsk GM:Ed Wright wrote: ↑Sat Sep 22, 2018 11:56 amWhy would anybody put a high volume pump in a SBC??gnicholson wrote: ↑Thu Sep 20, 2018 6:44 pm you installed a hv pump and you dont understand why the pressure is to high with your stated bearing clearance?
ZZ383_oil_pump.png
HV_oil_pump_PN93442037.png
https://www.chevrolet.com/content/dam/c ... 301295.pdf
https://www.summitracing.com/parts/nal-93442037
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Re: Excessive oil pressure
The picture used was from Summit; here are a couple from Jegs:
https://www.jegs.com/i/Chevrolet-Perfor ... 7/10002/-1
versus
https://www.jegs.com/i/Melling/689/M155/10002/-1
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