http://www.shell.ca/en/products-serv...power/faq.html

"Shell V-Power premium gasoline in Canada does not contain ethanol."

 

So what is better for a new 911....shell 91(no ethanol) or petrocanada 94(with ethanol)?

 

Based on the issues in the marine industry. I prefer, when possible, to use ethanol-free gas. That being said, ECUs adapt to octane sensed , so will run just fine with both. My old turbos need the higher octane to prevent inadvertant detonation under boost, so I'm caught between a rock and a hard place. Love going to the Dragon, where there is a station that sells 104, no ethanol

 

Depends on province I believe.
Ultra 94 has ethanol in Ontario, but not Quebec
Petrocan's also sells Superclean 94 which does not have ethanol, you can get that out west.

 

In California, Porsche's largest market, the best gas you can get is 91 with 10% ethanol. I have a ton of friends with Porsches in the bay area from 80s 911s to 987 Caymans. And no one has issues. So its pretty safe. When storing a car, I go ethanol free (Shell 91).

I saw dyno charts between 91 and 93 octane on a tuned 993 and they were losing about 5% hp/tq due to the retarded timing on 91. So on a 991 S, that could be 20hp. Its probably not that much, but there is a difference for sure. Or at least I *think* I feel one. Its probably a MUCH bigger difference on turbo cars tuned for 93.

 

My understanding is the 91 at Ultramar and CTC are ethanol free.
Very important for the 2 stroke toys.

 

I heard the same thing Greg. Something about government mandate. They couldnt get around the loophole anymore of averaging across all grades of gas. Not sure though . It was on the internet however so it must be ture. People dont lie on the internet .

 

I have heard Ethanol is an issue for CIS cars because ethanol attracts water, and moisture and CIS systems dont get along. Plus I can't imagine ethanol reactes well with rubber and plastics not designed for it from cars built 30+ years ago.
Also keep in mind ethanol will do its worse in humid enviroments as it will atract moisture in gas tanks being vented in humid weather , as gas goes down in the tank humid air is pulled in.
For its heat California is not nearly as humid as we have here for example, or god knows Hong Kong for example . Thats when the ethanol will pull moisture.
All that said i have never had an issue with my car and i run all kinds of fuel, in the really hot weather i will run shell v- power to just regular plain old 87 during cooler wether ( my car doesnt call for premium or even mid grade ) the 78 and 79 is farly low compresion ratio engine so the demand for premium wallet emptying fuel just isnt there.

The only time i really hunt for ehanol free gas is when i am about to store for the winter .. then its shell V-power all the way ..
plus they made that awesome Ferrari commercial ..



Not making any drastic statements or recomendations, just a few points to consider.

 

I have used Shell 91 exclusively in my cars and had not problem

 

it doesnt though. 30km difference is so little it couldve been a difference in weather, how your trips were etc.

 

Maybe because it's a turbo but my baby's mileage is about 15% better using Shell 91 without corn syrup vs Petro Can 94 with corn syrup. Excellence Mag. says corn syrup is not good for any Porsche engine so avoid it if ya can.

 

Anyone notice Shell brought back the locking gas handles?
Don't know 'bought the competitors yet.

 

Key word here is tuned... Unless you advance timing or physically increase compression ratio to make use of the octane rating, you won't actually have any performance increase when changing fuel types.... This is a common mistake. You can't simply put in higher octane fuel and expect to have more power or better fuel economy...

Octane rating is simply a resistance to pre-ignition. To make use of the high rating you need to physically change something with your engine (timing, etc) otherwise this is pointless...

Most fuels have the same specific energy, it's the resistance to pre-ignition that allows you to advance the timing and raise compression ratio and better control the combustion process to squeeze a little more power out of the engine...

JR

 

Right, modern 911s are tuned for 93 octane, so at 91 you are running retarded timing. For older 911s (basically all air cooled), its simple, don't run ethanol since your car doesn't support it. But newer 911s you're stuck between a rock and a hard place... run ethanol or retarded timing (3-5% power loss).

 

Are octane boosters ethanol?