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I have a 2017 CS with Sport Chrono. When positioned in Normal mode the oil temperature runs about 18-20 degrees higher than in Sport mode. It is very consistent and independent of steady highway driving or suburban stop and go. Flipping the spot mode on always causes a 20 deg. rise and flipping it off causes it to drop back down.

Not sure of the engineering intent behind this. I am guessing sport mode increases flow to the oil cooler for some reason. Maybe the lower temp in sport mode creates greater thermal margin for spirited driving that might be anticipated when it is switched on.

Just a curious engineeer here.
 

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I have a 2017 CS with Sport Chrono. When positioned in Normal mode the oil temperature runs about 18-20 degrees higher than in Sport mode. It is very consistent and independent of steady highway driving or suburban stop and go. Flipping the spot mode on always causes a 20 deg. rise and flipping it off causes it to drop back down.

Not sure of the engineering intent behind this. I am guessing sport mode increases flow to the oil cooler for some reason. Maybe the lower temp in sport mode creates greater thermal margin for spirited driving that might be anticipated when it is switched on.

Just a curious engineeer here.
I've posted about this elsewhere, both on this forum and on Bimmerpost:

The engine designers program the engine to operate at significantly cooler temperatures in more performance-oriented "Sport" modes: in fact, the higher the mode, the cooler the engine is designed to run. This is because it is assumed that the engine will be operated in more extreme and stressful ways in those higher "Sport" modes: -- i.e. performance driving -- and the cooler temps are the engineers hedging their bets on forces out of their control -- i.e., ambient temperature, stop-and-go city traffic with little radiator airflow, etc. This is particularly important for turbocharged engines with limited cooling capacity, like those on the 718 and BMW's equivalent 4- and 6-bangers.

There's actually a good discussion about the engineering reasoning in the F30 (BMW 3 Series) technical manual, particularly regarding the N20 and N55 engines. I'd link to it, but to my knowledge it's not available free-to-view online. On the N20, the engine is designed to run 10-12 degrees F cooler for every step up in engine mode (Eco Pro, Normal, Sport, Sport+). I've confirmed that behavior in my 2 Series with an N20 engine using a P3Cars gauge.
 
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I'm not certain about the 718, so apologies if this turns out to be wrong....... The 981 GT4 operates similarly and it is through the use of a map controlled thermostat. the thermostat includes a heating element to alter the operating temp. If in normal mode and the car is driven hard (high rpms) then the map will shift to a sport mode with lower temp.
 

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Hi all. First post here. I recently purchased a new 718C and am struggling through the break-in period. I also noticed the oil temp behavior and was wondering about the mechanism behind it. Coolant temperature remains consistent either way. Looking forward to learning more about the technical details of the car. It’s also my first Porsche.
 

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My 981 Cayman GTS runs cooler in sport +, my understanding it is because it makes use of the third radiator ("I read it on the internet").
 

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If the car is running cooler when in Sport, you are not driving fast enough. Go back to Comfort mode. ;)

I kid, I kid. It does that even when you are canning it for everything it is worth at 100 degrees tarmac temperature on the racetrack. Reasons behind it are unknown to me, but I am VERY glad it does that while on racetrack.
 

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Hi all. First post here. I recently purchased a new 718C and am struggling through the break-in period. I also noticed the oil temp behavior and was wondering about the mechanism behind it. Coolant temperature remains consistent either way. Looking forward to learning more about the technical details of the car. It’s also my first Porsche.
Don't suffer. Will you adhere to NorthAmerican manual or choose to use rest-of-the-world manual (no stated rev limits) - the car will be fine either way
 

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This behavior is very well known, and the only logical explanation I see - is that Porsche chose to use sub-optimal temps in order to satisfy EPA, greens, etc, to get that 0.001 extra mpg and 0.0001g less CO.

My reasoning?
1) The whole "lame" (also know as "normal") mode is only there on our sports cars because of green regulations.
2) Running engine cooler is better. That's why we have radiators :)

Adding 1 and 2 - the only conclusion I see is that running engine hoter is somehow better for fuel and emissions.

By the way: T-Design memory module takes care of that problem. Among other things - it allows you to run your car in the right mode all the time. Run your engine cooler without you having to remember to push that button every time!
 

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Sport Mode, when engaged, allows the heat exchangers (coolant/oil) to shed oil heat via the cooling system--to the tune of about lowering the oil temps at the track probably 20 degrees.
Regarding oil temps at the track with a 718, what are you owners seeing?
I ask since when I test drove a 718S on a very hot day last year the oil temps hit 250deg. in street driving--compared to about 230 deg. in our 981S.
 
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