yeah my pressure at WOT is around 55-60 and when i am just sitting in traffic or somethin on a hot day its about 25 psi just sitting there but gets up there if i go WOT even when its really hot and the engine temp is about 210. but just crusing its about 35-40.

 

look at this it might help and clear up some things

 

great thread guys....
I am also having this problem. After a head swap, i lost an oil pump. Put in a new one and started having pressure problems. At cruising it was only around 20psi(still within the 10psi/1000rpm). Changed the oil and had a **** LOAD of stuff in the filter....our guess was that it was material from cleaning the deck. Afterwards, pressure was good. 40spi at cold, 40spi at cruising, but as it warms up, the pressure drops to 25-50psi at idle, but holds good pressure at WOT and crusing. I think it just has some material on the pick-up.

 

i had the same problem on a gen1 sbc in a truck. i dropped the pan to discover that a bunch of permatex had been sucked into my pickup tube screen, restricting flow. so i cleaned the screen, filled the pan with 4 qts oil and halfass bolted it back to the block, pulled ignition wire and ran the starter, turning the motor over for about 2 minutes total, 20 sec at a time...as not to overheat starter. pulled the pan again and the screen was blocked AGAIN. when i was done i had literally a handful of **** including paint chips from the last time...i didn't rebuild the motor the 1st time, but i did the second time. the dude repainted the heads...SPRINGS AND ALL.

 

As far as oil pumps go I have seen VERY few problems with the stock pumps that come with the 01-02's.........

 

so has anybody swap out the slp pump and fixed the problem?

 

I should have mine swaped out next week. I am waiting for parts to arrive.

 

let us know.

 

What did you guys use to lubricate your new oil pumps before installing? I bought the GM LS6 updated version for my '98 and its bone dry with no lube.
Thanks

 

I don't know what it was, but I dropped the pan and there was a grey, pasty, filmy residue on the pickup?? I don't know what it is? Everything else looks clean, I cleaned it off and everything is fine. I assume that something happened during the swap? There was not much to clean most things were new. Anyway, I am very relieved, oil preasure now goes to 70+ at high RPM. Good luck to everyone else, and thanks!!!!

 

Has Any Body Figure Out The Problem With The Oil Presure Dropping

 

OK, I have replaced pump and cleaned the pickup screen. My pressure has increased from 18-25 psi at WOT to between 35-45 psi. The thing I don't understand is that on cold start up the pressure is 55-65 psi. Driving around with oil temps in the 180-200 range pressure is 45-60 psi. Hot idle is 29-33, as soon as I get on it pressure drops from 50 psi down to 35-45 psi range. I just cannot explain this?

I did find some trash in the pick-up screen which I think has helped with the pressure increase. The pressure is higher, but I would like it to be in the 55-65 psi range at WOT.

Am I correct in saying that a built motor will have less oil pressure than a stock motor do to loose clearance for high rpm use?

 

Can anybody explain why my pressure is good during start up/normal driving and sux at wot?

 

I want to bump this to find out the cause also.

 

Anybody?

 

I took the pump apart and lubricated it with motor oil before installing.

I ran my car probally 15 more times at the track and have had no problems with the oil droping in the 18-25psi range. I would like it to be higher than than 35-45psi at wot, but I think with a big cube motor maybe that is normal. Nobody, has replied to the post so I really don't if its OK or not.

 

I disassemble them and coat the inside of everything with motor oil.

 

Mine did that at WOT when it was 1 quart low.

No. It if it is built correctly it should not. My LS2 402 has over 40 psi at hot idle and 60 psi at a steady 70 mph. It has a stock, unported new pump.

 

Mine does the same thing when low on oil. At wot in 1st gear the oil pressure drops as the rpms go above 5k. When I go wot in 2nd gear everything is fine.

I thought it was from the oil pick up being in front and the oil sloshing towards the back during hard acceleration.

My car did this before the cam swap.

 

I know this thread is old, but I would like to let people know what my oil pressure drop problem was. I had my 427 C5R blocked motor built, installed, and tuned by a sponsor of this site about 1 1/2 years ago. I have never felt comfortable with the oil pressure on this motor from day one. I installed a QTP high volume oil pump and used 50 weight oil and my oil pressure did increase a little, but it still was not were it should be.

I decided to pull the motor out and install a 402 LS2 and rebuild the 427 and install it in my 67 Firebird. After pulling the 427 out and inspecting it, I found that my oil pickup tube was sitting on the bottom of my pan with no clearance. This would explain why everytime I would go WOT my oil pressure would drop. When I installed the 402, I modified the oil pickup tube for clearance my oil pressure is rock solid.

Just wanted to let people know to check oil pickup to pan clearance on these big cube motors.