Just curious if anyone else with a ZZ4 short block have had low oil pressure concerns at idle?
Mine has less than 2k on it, and the oil pressure at idle is about 13-15psi hot. When cold its about 40psi.
Highway cruise is around 40 psi also when hot. My old motor and every other car I have has at least 30psi at idle hot.
This is with 10w-30 oil.
My old motor with 100k on it that the ZZ4 replaced had about 25-30 psi at idle, and its the same gauge/sender so its not the problem.
Thanks

 

My oil pressure stays up around 60 cruising after warm-up. Drops to around 40psi at idle. Engine has about 40k on it.

 

Im not sure h ow true it is, but i have been told that you only need 10 psi for every 1000rpm your engine is turning. If that is ture then you would only need about 7 at idle. But like i said, im not sure how true that is. I know you can put thicker oil in it and that will make the oil pressure go up some

 

I'd like to see at least 30 psi at idle, I never had a car that wasn't at least that. I have noticed I can drive and get the emgine temp up to normal and it will still be at 40+psi, until I rev it higher than 2500rpms a few times, then it starts going down after that.
Kind of seems like the oils getting airrated by the crank, but its not overfilled.
Checked the level both when cold and when hot when the pressure has dropped and its at the perfect full mark.

 

I would put a mechanical gauge in just to see. Just because you are using the same sender doesn't mean it is correct. Also GM says you only need 10 psi per 1000 rpms. Look at it like this, the more pressure you have the more horsepower it takes to turn the pump. Volume it the real key, not pressure. My guess is you actually have more psi than you are seeing.
"If you don't break something, your not running fast enough!"