Alright so I have a built b-ls with a itr head and the whole shabang. When I first put the motor in and primed it, after first startup oil pressure was pretty good. around 10 psi @700-800 rpms. During break in and currently, I am having low oil pressure around idle, but within spec through the rpm range. Cold start pressure is fine, but when its fully warmed up and hot at 1k rpms oil pressure sits around 4-5 psi, and 9-10 at most. Sometimes at 1500 rpms when i lock the idle there oil pressure will be between 14-11 psi. Cant seem to figure out why, I have an idea, but I dont think it would affect pressure that much, as I believe the plug on the bottom of the head is leaking, as well as the distributor. I dont want to just rule that out but I need advice. switched to 10w-40 a while ago and it brought it up by 2psi. Anyone have any ideas? any insight is greatly appreciated

 

What brand of main bearings did you use ?

 

King enginesbearings

 

i also dont want to not think its the bearings, because of the leaks i have. anyone?

 

Top end leaks do NOT affect bottom end oil pressures... just because you don't like the answers doesn't mean they don't have merit. You used questionable bearings for your application. You must consider it.