Correct,

All NA imported vehicles from Germany will have the AKI rating and not the Euro rating.

Mine specifically calls for 93 Oct AKI, min is 91 Oct.

I get low speed ping with the SRS in California and AZ using their crappy 91 Oct. (A guy was randomly posting about this in the 718 section recently too)

 

Heres a good link for the conversion

Octane conversion chart US vs EU | BobIsTheOilGuy

 

Time to fail tech inspection!

 

It will retard timing when it detects knock to prevent catastrophic damage, but it has to detect it first; it's still not ideal. Better to run the fuel the car is tuned for.

 

Madam / Mr. Essaie you are making a little mistake when reading the sticker on north american pumps and the fuel door on your car. Our 911 fuel door sticker reads RON+MON /2 =93 which means research octane number + motor octane number divided by 2 = 93. We average the research and motor numbers to come up with an octane #, the lazy, slacker Euros just use a single test of the higher ROM#. Our 93 is the equal to their 98 and their door stickers correspond to that.

Since you live in Victoria at sea level the air is denser and on a cool day your 987 could make more power with the higher octane fuel. If you lived in Calgary at 4400 feet with the corresponding lower barometric pressure, the MAF sensor would mix in less fuel and the engine cylinders would see less brake mean pressure (less power) the 93 octane would not make any difference. In the higher elevation ares of Colorado they even sell a 85 octane as a base fuel.

In our 997.2 GTS, I never get the throttle much past half way or never see much red line action, so any old gas is probably good enough for me. However I always buy the good gas, because just because.

 

FWIW I've data-logged gas from multiple BC and WA stations in turbo and NA cars. Prior to Chevron adding ethanol to their 94, Shell 93 was consistently the best, ie. best at resisting knock. Chevron 94 was generally second, though I've found it to be more variable than Shell as well, and close to Shell 91 in knock resistance. I haven't re-tested in the past couple of years since they added ethanol to the 94 though; it's possible that has improved its performance. That said, if you drive an NA car with the stock tune, any decent 91 or greater should be fine. For turbo or tuned cars though, you want Shell 93 and/or Chevron 94.

While the average of RON and MON is theoretically supposed to represent the anti-knock capability, as I understand it in reality the RON tends to have a greater effect, which is most of why two fuels can have the same "octane" while one actually does a better job of preventing knock. (Which means you can run more boost and/or timing.)

 

My cayenne has both
in R+M/2 91
Min 95 RON

 

So then is 91 safe for us or should we be doing 93?

 

Read somewhere that Shell 93 has more ethanol than the 91 to get it up that extra 2 points. Shell won't tell me. Please discuss.

 

Likely, that is where most of the extra often comes from.

Wish they’d do e30 at the pump, it’s like running race gas.

 

There’s a gas station north of Detroit that sells 100 octane race gas at the pump - problem is that you burn a third of the tank on the way home