Oil pressure issue is: at idle I have 59psi.. At about 4000-5200 rpm oil pressure seems to hunt between 45 and 65 psi...Pressure gauge is a manual style taken from pressure port at the oil filter boss..oil flows to a remote set up of duel HP1 filters.  engine is a GEN VI ZZ502....max RPM of 5200.   manual gauge oil hose length is about 15 feet.  engine has just been pulled apart and inspected and reassembled...oil pressure had same issue when first purchased before disassembly...engine hardware appears to be sound with all tolorences well within spec...oil pump to pan clearance is correct and pickup is mounted tight to the oil pump...any thoughts from the forum??  

Just a thought,from oil filter boss to oil filter adapter or a little more towards filters have you looked for any in route restrictions? Driving while blind on this one,by the way you can be nice now someone responded to your question.    

HI,

I SAW YOUR HIGH PRESSURE CONCERN ABOVE AND WANTED TO FIND OUT YOUR LATEST FINDINGS.  I HAVE A 327 OUT OF A 65 VETTE (350 hp, HYD VALVES) AND AM SHOWING OVER 60 PSI AT IDLE,  SIMILAR TO YOURS.  MY  MOTOR REBUILDER (IT WAS JUST DONE) SAYS NO PROBLEM (HE PUT IN A HIGH VOLUME PUMP,  AGAINST MY REQUEST OF OEM PARTS).  I'VE READ MANY ARTICLES AND THEY, FOR THE MOST PART, SAY GO WITH THE OEM PUMP,  WHICH IS ONLY ABOUT 20 - 30  PSI AT IDLE (BEFORE THE REBUILD, ORIG MOTOR,  I WAS AT 32 PSI).   AT IDLE / 60 PSI MY PRESSURE GAUGE IS PEGGED ON THE DASH,  WHICH BUGS ME AND I CAN'T BELIEVE IS GOOD.    THOUGHTS ?
THANKS   MARK  

I have full flow -10AN oil lines in and out to duel full flow HP1 filters. I dont mind the pressure its the fluctuation at full throttle that concerns me...My engine building buddy of mine says it should be ok as long as it never drops below 30 PSI at full throttle...he also said to play with oil pump pressure spring to adjust desired pressure..I guess we(I) are looking for any direction to take from an oil systems pro..

Wieder, stick to the 305's obviously you have no knowledge about oil systems...I cant afford to run no oil pressure at 310 degrees for a second.  

does it have a baffle? windage tray? all that good ***  

No baffle , no windage tray....you may be onto something....what are your thoughts?....  

Attention bbfx88:You got some people mixed up, I'm not the person with the 310 degree 305!With out standing and staring at your problem in person and guessing what the issue is I would think you would be a little smarter than that. If you don't appreciate any advice don't ask!I've helped alot of people on here in a very short time and it's appreciated by most.Done with you!!!!!!    WIEDER  

one of these magazines just did a thing on the importance of a good oil pan and windage tray..and the motor also just happened to be a big block...they said they got a few extra pounds of oil pressure and got a little bit more power..i got the article in my room...I'll let you know what magazine it was and what parts they used  

Thanks for the help...when you find it let me know...thanks...

Wieder...sorry for the mis-statement...I confused you with some one else.....any help to my question is appreciated....  

it could be that the high pressure oil pump is pumping all the oil to the top of the motor at high rpm and it cant drain back as fast as it pumps it.you probley need a 6 or 7 quart oil pan. good luck with your project    

I mistated earlier, my oil pan has built in baffles and built in windage tray....also as last post stated I need a bigger pan....pan currently on engine is a 10 qt Dooley...I have been doinf some research on this site and it could be three or four causes...oil pump pressure relief, oil filter pressure relief, bad clearences on main/rods...the big question is to run or not to run with the fluctuating pressure 45psi-60psi AFT (5200rpm).  

It's good,not to many people do come forward like you did.Thanx WIEDER  

I have a Gen 4 454 has an M77 oil pump with 50-65 psi @ idle / cold or hot, oil pressure drops to around 10-20 psi after 28-3K rpm. Bring back to idle / 50-65 psi immediately w/ 40 w oil. A mention of pickup to bottom of oil pan was made / oil cooler system failure w/ 12AN line / not having windage tray / bearing clearances…..so on. The machine shop suggested thin oil (5-30w) to test the theory and can run thin oil due to tight bearing clearance. The oil psi would stay around 30-40psi cold at 28-3K rpm then drop to 10-20 psi  hot @ 3K- 4K rpm. One rule I’ve heard is 10 psi for each 1K rpm. There is 3/8 clearance off the bottom of the pick-up to the pan and crank clearances are @ .0018 rod and mains. The remote oil cooling setup has been removed and the adaptor plate was re-installed with a screw on “ WIX and/or AC Delco” filter to the block. I hear Fram is bad. This engine never had issues rolling down the track @ 7200 RPM w/ 60-70 psi all day w/ no windage setup. So far no metal in the oil filters since break-in ten hours on motor running. The only change has been the oil pan, crank and cam. The oil pan I ran before @ 52K and above all day long with out oil psi issues. This is the second pump same issue, and I’m getting ready to pull it again. I hope the above assists you with fixing this issue and shortens you testing. I think if your psi drops lower than 45 you might be @ risk @ 52K rpm and above for any long period of time.I’ll keep an eye on this forum and maybe I’ll have an answer after I pull/take apart the engine again or Machine Shop resolution, who are stumped at this time.

Scott
ckmate88  

Thanks for the help.  What I did is switch to different oil, Thicker.  and a smaller Fram oil filter....I was running duel Fram HP1 on a duel remote... with different oil and P8HA oil was steady 60 #'s all the way to 5200 RPM...I dont recall what my pickup to pan clearance is...
Let me know what you find....  

id have to agree, sounds like the HV pump is draining the sump under high rpm, i had a simmilar problem with a 350 that i built when i was in high school, more volume = better... not when your running a stock 5qt pan and no windage tray