Hi all,

I have a 991 Turbo that I just installed a GMG exhaust and applied a Stage 2 Cobb Accessport tune. I just test drove it and under heavy throttle it continues to get almost all the way up to the oil pressure read line continually hitting 58psi. Is that bad? Is that normal? Should I be concerned about blowing a gasket somewhere potentially?

I like to take this car to DE events. I am concerned if i run it like that for 3hrs a day it could be very bad for my motor. Valid?

Thanks in advance for your input and opinions.

CT

 

Do not know what the oil pressure call out is for your Turbo but for the 996 Turbo it is approx. 6.5 bar at 5K at 90C. 6.5 bar is 94.2psi. 58psi then is not *that* high.

At higher RPMs -- with my Turbo this is before 3K -- the oil pressure gage needle is at the 4 bar line, and 4 bar being 58psi. I can get a bit more oil pressure out of it -- so to speak -- with the needle advancing to nearly the "4.5" bar spot when the engine RPMs get closer to red line so for you to see 58psi at higher RPMs is I would have to believe normal.

Furthermore, I have driven my Turbo for hours -- until the fuel tank level gets low and I have to stop for fuel -- at 75mph+ and with the oil pressure showing 4 bar which is 58psi and the engine has never leaked a drop of oil. Well, the RMS seal leaked at approx. 120K miles but that's a seal that is not subjected to any oil pressure to speak of.

My non-professional opinion is there is nothing to be concerned about, but if you want some more assurance than I can provide stop in and arrange to have a Porsche tech road test your car and advise you regarding the level of oil pressure and RPMs and if there is any cause for concern.

 

Be thankful you have 58 PSI. An Exhaust will have zero effect on the oil pressure. I have my doubts that the tune included changing the Oil pump control. 58PSI is not low. These engines run lower pressures than what use to be typical. High pressure drains engine torque.

Just make sure you use the factory spec oil grade as this can change the pressure and cam control, but slight.

When you go to your DE event, always keep a good record of the Oil pressure and temps. Expect to run a higher oil temp at the track than on the street. Hot days will also contribute to higher oil temps. Be smart and use common sense. Keeping a record of the temps and pressure each time on the track, ambient temps and number of laps will allow you to gain some indication of how the engine behaves under DE conditions.

Have fun and enjoy.

 

To answer some of your concerns, neither the aftermarket exhaust nor the Cobb tune should have any impact on oil pressure.

The positive displacement pump in your engine builds pressure with increases in engine rpm.

Oil pressure is a function of other items. A rapid step change in "normal" oil pressure could be a failed oil pressure relief valve in the engine. Or, it could be a malfunction in your oil pressure transducer mounted on the engine. If that fails, indicated oil pressure usually drops off.

You can also expect to see some differences in oil pressure related to the oil you are running. 0W40 is less viscous than 5W40, so you should expect to see higher pressure on startup with 5W40 than with 0W40.

The question not asked yet is whether you saw a step change in oil pressure as soon as you made changes to the engine?

Lastly, as Macster suggested, 58 psi is probably normal for these engines.