K-A

I assume/d it's simply a "Temporary Sport Plus" so when I had a 718 S for a while, I just flipped the **** to S+ when I needed the boost (instead of using the push "boost" button). But then I heard that the button actually provides a MORE aggressive mapping than Sport+? Not sure if it was just marketing verbiage, but I'm curious of the same thing.

ace37

On the TT I know overboost is disabled in normal mode. The color of the boost indication goes orange when overboost is active. Now I’m curious to try S, S+, and the button all at once...

If you want a rough estimate of the power due to additional boost, with 420 bhp at 16 psi, taking atmospheric pressure at 14.5 psi gives a total pressure of 14.5+16=30.5psi. 420hp/30.5psi gives 13.8bhp per psi. Using that estimate, 2 psi means about 28bhp.

usccharles

That would mean be going from Sport to Sport + in a GTS is about the same difference in HP from going Carrera S to GTS. thats pretty significant to justify staying in Sport + all the time.

subshooter

Of course you are assuming a linear relationship between boost and HP. Maybe there is.

Mark993TT

My thoughts go out to everyone not going for the Sport Chrono package and missing out on all the extra horsepower in sport plus mode.

usccharles

on the contrary, if you don't have Sport Chrono, you wouldn't have all these different Sport modes, and while your throttle mapping etc will always remain same, I would assume you would also always have access to the full HP available for the particular 991.2 911 you own. but thats my guess. if you buy a 420 HP Carrera S, Sport Chrono or no, you should have 420 HP available. I think Sport Chrono is the one actually missing out on HP on some of its modes.

Mark993TT

If you don’t have sport chrono you still get the normal and sport mode.

usccharles

the non-sport chrono owners can help confirm but i would assume you would have reduced boost in normal and full boost in sport mode then

phx991

A few months ago you posted a thread asking how to "de-tune" your GTS, now you're complaining that it might be de-tuned?

https://rennlist.com/forums/991/1033...the-motor.html

Mark993TT

I really am curious how you guys do your real time testing. The only way to make sure what maximum boost the car is making in the different driving modes, is to put some load on it for a decent amount of time. Typically the lower gears are to short to do that. So that means you will have to be in a higher gear like third/fourth gear and above. What kind of speeds are you doing by then? Anyone tested this on the autobahn?

usccharles

i didn't post asking how to "de-tune" my GTS, I asked it would be nice to have a mode that "detuned" my GTS so I can drive my car in a more spirited way in the city. But, that is with the understanding that I would have full control and knowledge of when I'm in full power and when I'm "detuned" and by how much. with the current sport chrono package, no one seems to know definitively if the car is detuned at different sport modes and if so by how much HP. Porsche claims there is no "detune" of power in different modes but experience tells us that that may not be true.

this is two completely different issues. if you buy a 200K+ car and don't even know exactly what power you are pushing i think that is an issue.

You don't mind that your car has different HP levels at different modes without you knowing the full details??

usccharles

my next trip to track and and opportunity for some open roads on the way i plan on mounting the iphone camera so it records in slo-mo the dash and boost gauge and do a bunch of launch controls in all the modes and see how it boosts up.

but from my experience so far, it was hard for me to get to full 18 psi from just flooring the car even on Sport + mode, going through the ranges of 2nd 3rd 4th on the freeway floored. I could only get consistent 18 psi if i did launch control.

Mark993TT

Delivery date for my car is not until February/March. And I still have to run it in.

After that I will be more then happy to try some autobahn runs in the higher gears, because I think that will give more reliable data on boost levels.
Although I am still not buying into the detuned scenario.

usccharles

hopefully i can do some reliable tests for all of us before your car is ready to do your own. i also want to believe that there is no detune scenario

worf928

Boostgate.

How do you think Porsche produces an engine with an absolutely-flat torque curve from 1,XXX rpm to 5,XXX rpm?

By managing the boost level across the rpm range. A “purely mechanical” engine of any sort never, ever, ever has a flat curve.

There’s no fraud or deception here. Porsche didn’t sell you a torque curve or a constant boost level. They sold you a peak torque and a peak (flywheel) horse power number. You’re all hitting, at least, those numbers.