oil pressure question

[ViperRay]

I noticed at Hallett this past weekend that my oil pressure, which started out at 40 - 50 on startup dropped to about 20 after running the car ******* the track. It then came back up on cooldown.

I don't recall this happening on other track days but maybe I was inattentive?
I used 10w30 Mobil 1. The car also got hot (250) toward the end of each session.
It seemed like I spent more time at higher RPM's than usual (it's a short track at 1.8 miles and I spent more time in 2nd gear than usual). It was about 80 deg. out.

What's the likely explanation and potential cure? Change oil weight? It had me worried.

 

[Viper Specialty]

ACR Filter Adaptor will help in cooling the oil. Try a change to Mobil-1 0W-40 as well.

Radiator wouldnt hurt either...

 

[ViperRay]

The radiator's on my to-do list this winter. I have the ACR adaptor on already.

I wondered if the high engine heat was responsible and if a heavier weight oil would help.

What about 15W-50?

 

[Viper Specialty]

I would try 0W-40 first, it would appear to be a better all-around oil with the up-and-down temps you have in KS this time of year. If it still isnt enough, then jump to 15W-50. May be worth the money to invest in some type of Oil Temp Gauge? It would give you a better idea what is really "cooking" in there.

 

[Ulysses]

Oil pressure should read 10 Psi at Idle, 40-75 Psi at 3000 RPM. Check your oil level, you may have too much oil.

 

[ViperRay]

Could the gauge be off?

I usually run a quart low at the track since when I fill it, I then have to empty the puke can after the next session anyway.

As you know though, it's sometimes difficult to find a level spot when parked at some of these tracks so I might not have gotten an accurate reading.

 

[Ulysses]

I re-read your post. I assumed that you were reading 20 at Idle. If you got the 20 reading while moving in the LOW RPM range, not Idle, than I would say that you are OK. It's normal to read 40 to 50 at cold start up and then have it drop to around 20 during normal driving.

P.S. You mentioned you have the ACR adaptor on there. I'm not sure how that affects the pressure reading at different RPMs. My opinions are based on the standard GTS setup.

 

[Viper Specialty]

10 PSI is the bare minimum as per the manual- I have never seen one actually NEAR that low.

Lowest I have ever seen on any Viper in good condition is 25, even after beating the pants off of it. Most cars run 50-60 cold, 50-60 at cruise, and 35-45 hot idle.

 

[Tom F&L GoR]

The oil temperature gauge is the right start; depending on circumstances, oil temps could be lower, same, or higher than coolant temperatures. Many modern cars run oil temps between 250F and 270F, so don't let the higher numbers scare you, only guide you.

An accurate oil pressure gauge would also help the diagnosis. I know mine reads 7-10 psi lower than a mechanical gauge.

Also, pressure only ensures that the oil arrives at the bearing and isn't directly a signal that it isn't supporting the bearing/journal. The 10psi/1000RPM rule ensures the oil overcomes the centripetal (moving toward center) forces while inside the rotating hardware. Thicker oil puts up more resistance to flow, shows a higher pressure, but not always guarantee of better lubrication.