GreginNH

Not sure anyone else is experiencing this. The oil temps for my 2019 C4S are 18 to 20 degrees less than when in regular mode. Same RPMs and driving conditions for each mode.

Have any of you experienced the same thing?

Mike Murphy

I believe that is normal.

Jack F

Exact numbers I have not tracked but definitely cooler in sport mode. What was even more noticeable were oil temps in sport plus mode coming off the Nurburgring. Would be interesting to read how that all works.

BOPE

All three of my Porsches experienced lower engine oil temps in sport mode compared to "normal" mode.

I believe there is a thermostat in the oil system that "shifts" when in sport mode to accommodate the anticipated higher engine RPMs and thus higher oil temps.

Jason

rnl

it's because an oil cooler engages in Sport. You may also notice that the voltage increases too.

Rich_Jenkins

Yes.

217°F normally.

194°F in Sport.

My 981 Cayman S ran almost identical temps, IIRC. I could hear the oil cooler fans turn on if I was parked. Not sure if I hear the fans on my 991.2 but yes it runs cooler in Schport mode.

Mike Murphy

Correct.

An engine’s power increases as temperature goes from cold to warm, but at a certain point, it starts to go back down again when the engine is too hot. So sport mode puts you in a sweet spot by reducing temps a bit to keep the combustion chamber hot, but not too hot to affect predetonation. And colder oil gives more cushion/protection for extreme driving.

The tradeoff is efficiency and emissions. As temp goes up, emissions and efficiency go up slightly, as oil viscosity goes down - less drag - and exhaust temps are a little higher, so we get the best catalytic action.

The voltage increase is better for power because it results in slightly higher powered spark.

We are probably talking less than 1% with these changes, but hey, it’s “free” power.

So you now have a button that can control which option you want. The older cars (996 for example) don’t have any of this, but 20 years ago, we didn’t have as strict emissions regulations as we have today.

digits

I usually drive in Sport mode and unlike other cars the oil temp never exceeds 212 unless I’ve been driving hard. If it’s like that for too long I sometimes switch to normal mode to run at least in the 220’s for a while and boil off any contamination. I’m not sure if this actually beneficial or not, but it makes me feel better. Maybe one of our rennlist residents with more knowledge about motor oil can chime in.

Jack F

I went for a spirited drive today and pushed the car a bit. Oil temps stayed around 200F. 😉

Porsche_nuts

Why were you driving so slow?

pfan

Guaranteed to get the oil up to temp.

Valvefloat991

Actually, the thermostat in the water cooling system drops the water temp from about 220 to 180 when you engage sport mode. Y0u don't see this on the gauge because it is dumbed down and always reads 194, except when the engine is warming up or comprehensively overheating.

The oil is cooled by an oil/water heat exchanger, so when the water temperature drops, the oil follow accordingly. When running hard on the track, however, this heat exchanger can't keep up and the oil temperature rises again, but not as high in sport mode as it would in normal mode.

BSO

The articulated front bumper vanes are open on Sport settings, closed on O for gas mileage improvements.

I’m sure this affects the temps substantially. I drive on the Sport setting the majority of the time, my oil and water temps are usually in the 190s. If I push it, the oil temps will go to the low 200s.

I also own a ‘19 C4S.

Mike Murphy

The higher temp does technically increase the rate that moisture evaporates off the oil, yes. Moisture is still able to be extracted from the oil at lower temps, just like when you try to boil water on the stove, you see lots of vapor coming off the water at lets say 180F. The crankcase is under a relative vacuum as well, so that helps as well.

Regular oil changes are the only way to remove the contaminants, though, as those are left behind after the moisture is evaporated off.

GreginNH

Thanks for all the responses. Great info!