Aluminum Engine Oil Pressure

[fastlane99]

I just bought a backup motor that has 500 laps on it. Guy I bought it off of races in my area so I know the guy pretty well. Threw the motor in and at temp, the oil pressure is between 75-80 and at 4000 rpm the oil pressure is pegged at 100. What's going on here? Any ideas? Also at an idle, there is what appears to be a haze or smoke behind the car. The previous owner told me it did that before and the engine builder, who is a reputable builder said it was due to the type of valve seals they used and was normal at idle. Just seems like a lot of haze or whatever even when you rev it to clean it out. Just wondered if the carb needs looked at or if it is oil smoke or what. It is a light colored haze or smoke but doesn't readily smell like oil like I am used to. Any help or ideas with either of these questions would be greatly appreciated. Thanks

[grt74]

if it a dry sump engine i would check the spring in the pump,it sounds like it will take a softer spring,70-80 psi at 8000-8500 is what i like to see,some guys i know run a little less,but a good rule is 10 psi for every 1000 rpm,25-30psi at idle is ok when its hot(or after the race)

[cumminsman08]

Get your oil pressure down to what grt74 recommends i agree as well, try a different gauge/mechanical gauge just to be sure oil pressure is important so doesnt hurt to double check to make sure gauge is working properly.. 500 laps from complete refresh? Then figure out your smoke issue if its blue in color(oil caused smoke) find out exactly which style valve seals were used oring/ deflector seals or as i call them umbrella seals.. Good many laps maybe a few valve guides are worn..Wouldnt hurt to pull valve covers and go through the valve train if you have time, just start eliminating anything that the eye can see a lot easier on your pocket than running and doing trial and error usually isnt good on an engine.. Not trying to scare you or tell you what to do just letting you know what id do when buying a engine even though you've seen the engine being run..

[Brian Gray]

I don't even use seals on my valves an I get no oil smoke. You have a problem. A puff at startup is common but if its has haze there is an issue . you high pressure issue cold be culprit though. Get it down like they said 10 psi for every 1000 rpm is Smokey's rule .

[Brian Gray]

Also double check that your not returning scavange pressure. Believe it or not I've seen guys reverse the lines and pump the engine full of oil and air.

[save the racers]

I just bought a backup motor that has 500 laps on it. Guy I bought it off of races in my area so I know the guy pretty well. Threw the motor in and at temp, the oil pressure is between 75-80 and at 4000 rpm the oil pressure is pegged at 100. What's going on here? Any ideas? Also at an idle, there is what appears to be a haze or smoke behind the car. The previous owner told me it did that before and the engine builder, who is a reputable builder said it was due to the type of valve seals they used and was normal at idle. Just seems like a lot of haze or whatever even when you rev it to clean it out. Just wondered if the carb needs looked at or if it is oil smoke or what. It is a light colored haze or smoke but doesn't readily smell like oil like I am used to. Any help or ideas with either of these questions would be greatly appreciated. Thanks

We have been fighting an issue where we thought we had too much pressure. I would give it a try and see what it does after you run it hard for 5-10 laps and get the oil hotter. Did you buy the pump from the same person you bought the engine from?

[fastlane99]

No actually the pump is brand new. Hasn't seen the track yet.

[save the racers]

weaver bros pump?

[fastlane99]

It is a Barnes

[save the racers]

I would call and ask them, they should know best. We had ours backed out all the way and it was still 90+ but have also lost a couple. Hopefully we found our issues. Its tough to get the oil up to temp in the pits to give it a fair look

[Brian Gray]

You might consider an external bypass. Extra insurance rather than floating a bearing.

[jedclampit]

Oil,deposits from, in the combustion chamber causes pre ignition and detonation, and you know whats next. Get the plugs out in order, and pull the headers,look down intake with carb off.. Find the cylinder/s where it is, determine if it's guides or rings, leak down test for rings, if your real lucky an intake gasket. I can't imagine not having intake valve seals. Get a good look at them you may have one smashed or pulled up off the guide.

A dry sump pump will move some serious volume, pressure is a measurement of restriction. I suspect you either have a plumbing problem or pulley diameter problem (pump spinning too fast).If all checks out you will need a lighter spring in the relief.

Happy hunting.

[Necrosis]

Make sure that all the galleys in the block are properly restricted. Leakdown, vacuum, etc. What exact block?