Thread: Oil Pressure drop on RPM rise ?

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Running at about 3,000 RPM My oil pressure is about 48psi. Step the rpms up to 3500-4000 it drops to 40,It has not dropped below 40 and it goes back up whenI slow back down. What should I be looking at.

What engine? Stock or modified? Is the gauge reliable? Lots of variables here.

Mech or elec gauge ?

Elec Gauge, Gauge has been reliable, 383 ,Edelbrock heads, Airgap intake, Can't remember the cam specs at the moment

I would qualify the gauge before going further by checking it against a know working one, I prefer mech units but to each his own.

Assuming the gage is correct, I am thinking of a pressure drop in the filter causing this or oil is bypassing over a stripper valve in the oil cooling circuit before the gage if the engine has such.

Kitz

The gauge is good

Could be a few things, oil not returning fast enough to fully feed the pump (hvhp pump and stock pan) deep pan should cure this, oil foaming (no windage tray), oil caviting (try a anti-cavitation pump).

Originally Posted by 53 Willys

Running at about 3,000 RPM My oil pressure is about 48psi. Step the rpms up to 3500-4000 it drops to 40,It has not dropped below 40 and it goes back up whenI slow back down. What should I be looking at.

Do you happen to have a hi-volume pump?
Are you running a stock oil pan?
If you are I will bet you are sucking air.
Just like Viking say's above me.

Yes I have an HV with a stock pan , The 7Qt and pickup should be here on thursday and I will find out if thats it on saturday.

When you install the pick up tube, please keep it mounted as to where the thing does not touch the bottom of the pan. Volume will not be the ticket if the thing is starving for oil because of pan interferring with the capability of getting the oil to the pick up.

3/8-1/2" Clearence Correct ?

Thanks for the help. New pan and pickup-- It ran good pressure all day ,only problem I encountered was I had ordered a new pump with the pick up welded, got it in started the truck and only got a max of 30psi. Ripped it back apart. Ground the pickup off and put it on my old pump. Now I have a new pump with grinder marks and no pickup so I can't send it back.