hi8ha

Went to fill my truck at the Shell gas station I always use. Noticed a sign saying the gas, all types, has/is 10% ethanol, it was not like that the last time I went there 5 days ago. My concern is, can the 95 octane gas 10% ethanol be used in my MY99 911? It made no difference on my GMC MY99 truck.

1999Porsche911

No worries.

hi8ha

Thanks for the peace of mind.

bronston

You might find you mileage drop. There was madatory 10% ethanol from November-March where I used to live. I had a Taurus SHO back then and my mileage would drop from 22 to 18 like clockwork when the ethanol mix was used. It just doesn't have as much chemical energy in it as plain gas.

1999Porsche911

The most your mpg will suffer (if at all) is 1 - 2% using an E10 blend.

Ray S

+1

E10 won't hurt you....but, E85 will.

tooloud10

I doubt a single tank of it would, not that I'd try it.

Ray S

Long term there is little doubt E85 would be bad. Like you I wouldn't even chance one tank.

munro86

How much E10 is ok then? or is it just as risky as E85? and what are the actual risks?
Thanks.

Ubermensch

E10 is no risk at all as was previous stated. Use it to your hearts content.

David A

Any performance loss ?

tooloud10

^^^ There might actually be a tiny performance GAIN. Higher octane is a byproduct of the inclusion of ethanol in the fuel, though it would probably be imperceptible in an engine that wasn't designed to require it.

BruceP

In my experience, yes. The guys who work on my car won't race with methanol enhanced fuels. Although the octane rating is increased by ethanol (octane is not a substance, it's a property of fuel), it seems like some DMEs read the combustion of ethanol as pre-detonation and react accordingly, retarding the timing and enriching the mixture.

I've told this story before, so I won't repeat myself here. But the phenomenon has been proven to my complete satisfaction, and I avoid ethanol enhanced fuels like the plague.

1999Porsche911

That is hysterical. You don't actually believe what you just stated regarding the computer reading the combustion as pre-detonation, do you? Not using ethenol based fuels in a race car is because ethanol reduces the BTU of the fuel and therefore power per volume and not because there is any change in combustion. Methanol has an even lower BTU than does ethanol and is not used in E10. E10 fuel is perfectly safe for your car.

Indy cars have used ethanol based fuels for years......as well as methanol.

Sounds like the guys who work on your car were playing with you and seeing how much you would fall for.

ralundy

See any dictionary, octane is in fact the name of a chemical compound.