Just fired up my freshly rebuilt motor yesterday. Things are generally okay. Just some minor valtrain issues.

I am seeing only 30psi of oil pressure at idle after the car reaches full operating temp for a while. I re-used the old oil pump that only had 20k miles on it. I also re-used the o-ring which i inspected and re-installed carefully. Kinda confused as to why there is a problem.

Now on to the question. Which oil pump are people seeing the best results with? I want to order one tomorrow. I use to see no less than 39psi at any time at any temp and saw about 65-70 at WOT. Any recommendations?

 

What weight oil are you running, u could need a thicker oil, my old T/A would only get good pressure with 20W50

 

you o-ring could we a bit worn?

i bought a ported ls6 pump from TSP for 130, great service and fast shipping. bought a pack of 5 o-rings from gmparts direct. 50psi @ idle

 

I thought of that too. Certainly wasn't damaged to where u could see it. If I'm gettin in there I am not doing it twice...lol.

 

Depends on how the motor was assembled too... My stock motor idled around 38psi hot. I put in a stock, unported/unmodified LS6 pump on my new motor, and it idles around 50psi hot, hot cruise is always right at 58-61psi. This is with 10W40 oil...

 

Well I dropped in a ported TR l6 oil pump and shimmed the return spring .10" and got the same result as before. I talked to the engine builder who said that the 30psi at idle is fine as long as it is going up 10psi per 1k rpm which it is. He checked with the other builder there who all agreed. This shop does alot of ls1's so I'm going to take their word for it and see how it goes.

 

What are the increments for shimming the return spring to desired PSI output?

 

i don't know of any kind of chart or formula. You might make a seperate post asking what results others have gotten.

BTW, this did turn out to just be loser tolerances with the new shortblock. No problems so far with this setup(knock on wood).