Oil Pressure Question

[VENOMIZED03]

I have a question for you guys. I am attempting to make a LONGGGGG story short. OK...I bought a engine off of a person on this sight. Before I ran the motor I put a MS4 cam, spring, rods ect. on it. The motor has a LS6 ported oil pump and a LS2 timing chain. I get the motor all together and start it up. Oil pressure is at about 5-10 psi at idle and goes to about 20psi on a 4k rpm rev up. I am like WTF...So I go to the chevy dealer. Buy a brand new oil pump. Pull the damn pan back down and decide to take it off. The pickup was alittle clogged but nothing horrible. Clean everything up really nice, put the new oil pump on and get it all back together. Started the engine up again. Once again its at about MAYBE 15 psi at idle and MAYBE 30psi on a 4k rpm rev up. I know thats not enough PSI to feel safe. I dont know what to do. I would say maybe the gauge is bad but I hooked a mechanical gauge up to the car and thats how I know the exact PSI. Can someone please help me out alittle. I am stumped on what I need to do next. All opinions are needed.
THANKS JASON

[93lt1vette]

if there is nothing wrong with the pump or pickup (and provided those pressures are low I don't know LS oil press specs) it is possible the privious owner had his oil gallerys enlarged the larger area would allow for greater oil flow great for keeping your bearings clean and coold but can be a hinderance to oil press also esential to maintaining bearing oil wedge consider changinge to a high volume pump and if posible compare the manufaturer specs for flow rate. The other option is the press regulating valve that LS motors have is leaking by I cant remember exactly where it is in the motor.

[LS2Tuner]

Sounds SCARY LOW!!!!! I would pull the motor ALL the way down and get out a mic and dial bore guage and start measuring and inspecting all bearings!!! Not to mention checking ALL oil gally plugs are there.
Could be multiple things who ever put together fucked up!!!!:cuss:
10 psi. per 1000rpm is a generic guide line.

[Sarge]

Oh hell no...something is bad wrong....I idle at 50lbs and 70lbs at WOT with a Lingenfelter pump....something is clogged or not allowing oil to flow pass your guage....and critical parts for sure....

[SOMSS]

I idle at 65lbs and 80 lbs at WOT with a SLP ported LS6 oil pump.

[nc98z]

I have ran into something like this before. The problem we found was somebody put too much silicon on a gasket and it squezzed out got in the oil pan and would almost stop up the oil pickup when the car was running. Hope this helps.

[RRE101]

Hate to say it, but you can't ignore a bearing clearance problem with those symptoms on a new motor.

[sic2001]

did you ever find out what this was?My car is doing the exact same thing now after a cam/heads job

[Tracker9118]

You should have around (60 psi) at 4500 rpm

[LETHALxLS1]

did you ever find out what this was?My car is doing the exact same thing now after a cam/heads job

Did you put a new oil pump in it? I was talking to a guy on here and he told me there is a o ring on the oil pump pickup tube that needs replaced when you replace the oil pump or low oil pressure will result the part# is GM#12557752

I hope that helps

[sic2001]

thanks alot, were gonna put a melling pump in...along with a new o-ring. The guy who did the h/c job was a boob and a liar. He put a used pump in so Im sure used the same o-ring

[LETHALxLS1]

I hope that fixes the problem and if he put a used pump in he prolly didnt put a new o ring in(like u said). Alot of people overlook this from what I was told because the O ring can look fine but still needs changed. Good luck and keep us posted.