51 6 cylinder Flathead Oil Pres Question
 

Ok all you 226 7HA Flathead guys what kind of oil pressure is your gauge holding. When engine is warmed up I'm getting 20 psi at idle and 55 psi above idle.

I think the pressure relief should be set at 57 so it looks right to me. If those are "hot" figures then I believe that is real good. I don't have a mechanical gauge on mine but the stock electric gauge reads close to those same numbers and I know my engine is very tired! I don't think I have ever seen a bottom end that is any more overbuilt than the 226-H. That is a tough little motor.

51, you can be very happy with your oil pressure. I have a freshly rebuilt 59A that has good start up pressure (50 lbs.) . At prolonged idle it drops to 7 psi. I know a knowledgable ex flathead racer and he says that if you have any kind of pressure at all at idle (5-10 lbs.) it is adequate. He,s given me much valuable info over the last few years and has not steered me wrong yet. Steve

Anything more than 50 psi is a waste; it takes horsepower to pump oil to pressure. I concur that 5 psi at idle is adequate for a warm engine.

Thanks guys for the input.