the weird thing is I had straight 30 in it for break in. The pressure guage was around 50lbs and never varied. I bought another guage to check against it and it seems to hold steady at about 40. no fluctuations with RPM. I'm beginning to wonder if my pressure relief valve isn't working. New Melling pump.
you have to love manufacturing tolerances. unless your gauge is calibrated to NIST standards, then the best you can get is an approximation of pressure. if one gauge measures 40 and one measures 50, then you have about 40ish to 50ish psi
As far as oil goes, only oil rated for diesel still has zinc in it. Its what I have to run in everything I own.
