Oil Pressure ?

I need some answers ... I know This is the right Place so here goes ;

My oil pressure idles between 15 - 20 and normal driving between 40 - 50 .
But when you really get on it my oil pressure gauge bounces between 20-50 and as soon as you let out of it it stabilizes back between 40-50 . What could be causing this ???? No Windage Tray
I haven't driven it since this occurred . Don't want to Mess anything up
Engine specs;
514 CID
Scat crank
Scat I- beam rods
Icon flat top forged pistons
Total seal Gapless top ring
Melting high volume oil pump
Comp hyd. Roller murther thumper cam
Edelbrock alum. Heads. With Mild port work on Intake & Exhaust
Comp Ultra Gold Roller Rockers
Air Gap Inake
Quick Fuel Carb 950

Did you make any modifications to the oiling system or bush lifter bores as part if your build? Which hydraulic roller lifters are you using?

No oiling modifications , did nothing to the lifter bores and am using Comp Cams roller lifters , when I ordered the cam they matched the lifters for me .

If the oil pan is a front sump type most of the oil is flowing to the rear when you "get on it" and the pickup is uncovered enough to where the oil pressure drops and the gage is bouncing around. This is elevated where the roller lifters tend to be not good with oil control and most of the oil is up top. The fact that you still have oil pressure may tell you that a windage tray and deeper pan may solve your problem.

If you got a rear sump pan then I dont have a clue as to whats happening.

Thanks Dave . Yes it is a front sump pan. Guess the engine is gonna have to come back out to fix the issue

Jimmy how many qt of oil you running if you are running 5qt you probley running it out of oil what I have been told you need atleast 8qt try adding a 1qt or 2 of oil and see what it does.

Thanks Jim . I was running about 5 1/2 but I did add another quart but haven't driven it yet. Oil level is showing just a hair above the safe mark on the dip stick

add two more quarts

Thanks BossHoss
Going to add them in the Morning when I get off work

bosshoss wrote:add two more quarts

X2,and If you don't have the front drain back holes in the block the HV pump will suck that little pan dry before the oil can get back to the pan.

windage tray it get even worse with rear sump pans, without a windage tray...also you haven't enough oil in the crank case....

i'd try another gauge first.......

What is the pick up to pan clearance set at? I had a similar issue once when the clearance was too tight. I would try adding some oil first though.

Dave De wrote:If the oil pan is a front sump type most of the oil is flowing to the rear when you "get on it" and the pickup is uncovered enough to where the oil pressure drops and the gage is bouncing around. This is elevated where the roller lifters tend to be not good with oil control and most of the oil is up top. The fact that you still have oil pressure may tell you that a windage tray and deeper pan may solve your problem.

69F100 wrote:Jimmy how many qt of oil you running if you are running 5qt you probley running it out of oil what I have been told you need atleast 8qt try adding a 1qt or 2 of oil and see what it does.

bosshoss wrote:add two more quarts

bbf-falcon wrote:

bosshoss wrote:add two more quarts

X2,and If you don't have the front drain back holes in the block the HV pump will suck that little pan dry before the oil can get back to the pan.

the Coug wrote:windage tray it get even worse with rear sump pans, without a windage tray...also you haven't enough oil in the crank case ....

bigblok2000ranger wrote:What is the pick up to pan clearance set at? I had a similar issue once when the clearance was too tight. I would try adding some oil first though.

It seems most agree the oil supply to the pickup tube is not adequate!
Dave.

First off I want to thank everyone who has commented to help solve my issue .
I added 2 quarts of oil this morning and drove it the only difference now is that the gauge is Not bouncing around when I really get on it . It drops down to 20 psi and stays there until I let out of it then goes back to around 43 psi . The oil pump and pickup tube is exactly the same as my other 466 is with NO issues with oil pressure . Don't know what I am missing

Two possibilities, (1) Comp Cams gave you small block lifters - dimensionally identical to big block lifters, but the oil feed hole in the lifter body would be facing the feed hole in the lifter bore, flooding the top end. Correct orientation has the feed hole in the lifter 180* from the feed hole in the lifter bore. I know this because I sent my lifters to Comp Cams to be rebuilt, and they sent me small block lifters in exchange. I didn't catch the error until a year later when I went to install them in a new build. (2) You may need a restrictor style push rod such as Smith Brothers to reduce flow to the top end. A lot of guys say it's "just a band aid fix" but it worked very well for me. At WOT I could pretty much drain my oil pan in a quarter mile.

Wayne (SAWDOFF) Pearce

The HV pump may be part of the problem. With pressure in the 40 - 50psi range there is probably reasonable clearance on the bearings so a lot of oil getting around the engine and the pan running a bit dry or aerating the oil.

I had a similar problem with a Cleveland a while back. The solution was a standard volume pump, a Moroso pickup (the box type ones) and filling the pan to the second 'L' on the dipstick where is says 'Full' above the mark. Problem solved. My Cleveland is running a big sump with 8 litres in it.

I fought this on my first stroker bbf build. It wasn't as drastic as your issue... I'd notice the pressure falter around a bit in the top end charge at the strip. I was putting all of the oil upstairs and it wasn't draining down to the sump of my deep pan (front sump) quickly enough. Windage tray was not helping. I machined evenly spaced holes in the winage tray to allow the oil to drain back down thru them rather than have to ride on top of the windage tray foward to the sump before falling. This helped dramatically. To stick a fork in it I ended up going with a Kasse pump. No more issues.

You could also be aerating the oil. You are now running a longer stroke crank than the 466ci deal. Maybe time for a deep sump pan.

I had a similar issue with a 532 on the dyno (eliminates oil climbing out of the sump due to acceleration...). I couldn't get my hands on a Kaase pump so we replaced the HV pump with a standard Mellings. This took care of the issue so it appears I was pumping all the oil up top and it didn't return to the oil pump suction fast enough (or possible aeration).

had this same issue on my fox body. ended up being overfilled on oil and when i was on the throttle the oil sloshed to the rear and the crank hit the oil causing aeration. i have a 6qt pan and i only run 5 to 5.5qts to solve the issue. instead of over filling try under filling a bit and see what happens.

Jimmy you ever figure it out

Kaase oil pump

What pan are you running?

Jim , I haven't had the time to mess with it much Been stuck on the Graveyard shift.
Dfree , it is a stock pan front sump .

It's a windage / capacity problem get a tray and a good deep aftermarket pan with baffles.

Overfilling the stock isn't the solution, it will cause aeration problems.