Over the years, and since the launch of the 991.2 T in 2018, we’ve heard over and over from those actually DRIVING the car that is “feels” quite more spirited than the base. To which the naysayers have always responded that I couldn’t be, since it has the same engine, and 11lbs would not make any difference at all.

Well, according to an internal Porsche document, it shows something quite perplexing: the MPG of the manual Base vs the T is 28.3 vs 24.7, which is a HUGE difference! We could argue that perhaps the different gear ratios of the manual T va the Base is the reason, but here is where that explanation falls flat: the MPG of the PDK Base vs the T is 31.8 vs 27.6, which is an even greater spread, when the PDK on both are THE SAME!

So, my conspiracy theory, as imagined by many of us who have experience this performance difference, must be due to an undisclosed ECU programming difference.

Otherwise, how do you explain a more than 10% loss of mpg efficiency from a lower weight vehicle???

So, let’s hear your ideas of why this is.

Ah, and here is the picture of the document to avoid any misunderstanding.

 

Check the published CO2 emissions per g/km of both. That’ll give you a clue as to whether the ECU is tweaked

 

I could have sworn the final drive ration is different. Higher final gear would make quicker at lower speeds but slower at top speeds

 

Good shout. I’m reading 3.59 for the T and 3.44 for the base. Can’t confirm tho

 

I would not be shocked at all to learn that the gear ratio is 100% of the difference.

 

You are correct regarding the final drive ratio for the MANUAL, but not the PDK! Why would the PDK be also impacted by more than 10%?

 

I'm trying to dig up something more concrete, but so far I'm finding that the PDK is just like the manual transmission in that it has a base model and an S/GTS variant. An old thread also indicates the final drive is different in the PDK, just like the manual.

 

So, if anyone thinks this difference is due to the final drive, which is supposed to be the same as the S, then… WHY is the T still delivering lower MPG than the S????

And this is the official website from the EPA:



MPG numbers for the PDK transmission Base/T/S







MPG numbers for the manual transmission Base/T/S


It has to be a hidden tune…


Enough to convince you now?

 

Not sure but t’s have been known to dyno between 350-360whp on a dynojet stock. Anyone have a base dyno to compare? My guess is it’s very similar.

 

Makes no sense at all. Even if the ECU were tweaked, the difference woudl be at full-throttle and high rpm, not at the mild loads used for the fule economy tests.

 

Maybe the engine mounts being located in a different place?🤣

 

Not necessarily, you can tweak the ECU to alter the response at any RPM you want and have unique acceleration curves.

Otherwise, how do you explain this big difference between the T and the other two?

If the T had worse MPG than the base, but similar to the S, it could be the gearing, but why is the T’s MPG more than 10% LOWER than BOTH the Base and the S?

If it was heavier, perhaps, but again, it is the lightest weight of the 3 of them. Or if it had a crazy ducktail or funky aero, but there’s none of that, that is why this question is killing me, hahaha.

 

When Porsche creates a special model they tweak everything to accomplish what they want. So that will include but not be limited to the ECU, spring rates and shock valving, sway bars and engine mounts, steering sensitivity etc. The mix is almost infinite, which is why they do such a great job with every model type. Each is catered to the type of driver they think will be a buyer.

 

T is not a special model it is a package…
it is what it is, enjoy it for what it is.
as long it makes you feel special.

it’s the base engine period… I’ve driven one and than hopped back into an S which was significantly better on acceleration and braking.

 

Same engine with a completely different MPG rating for no reason whatsoever…. Ok.