Which would you use?

91 Octane non-Ethanol gasoline or

93 Octane gasoline with up to 10% Ethanol added.

I can get both at a station near my home.

The non-Ethanol gasoline is about 30 cents more expensive but that really isn't a factor for me as I don't expect to drive the car that much.

 

Octane matters. Go with 93. 91 octane will cause the timing to be adjusted and will decrease performance

 

^+1 yup octane matters so if 93 octane NO ethanol (which is what I am lucky enough to get and use) is not available go with 93 ethanol (yuk!) gas.

 

Get the Pure Gas App and use it to find 93 100% gas in your area.

 

As a petroleum engineer, just hearing the world ethanol makes me so damn angry..
But octane does matter. I wish CA had 93.

 

93! Both the ignition timing and injection is modified when using 91 and lower. Not good for the engine.

ChuckJ

 

I can get racing fuel here in CA. Does it make sense to mix it with 91? Say 3/4 tank with 91 and 1/4 tank 100.

 

Not unless you are tracking the car. 100 octane gasoline is expensive and if you drive any miles at all your gasoline bill will reach the sky.

If you are not driving many miles the 100 octane gasoline goes stale and some of that 100 octane benefit goes too.

Just buy a top tier 91 or higher if available (up to 93) gasoline from a busy station and relax.

 

The US is Posches biggest market so don't you guys think theyve designed an engine that can use ethanol without any problems?

 

There was a discussion on ethanol infused gasoline and what it does to your engine in a recent local PCA forum here in the Dallas-Forth Worth area (Maverick Region PCA). I am sharing this for Informational purposes:
1. http://video.foxbusiness.com/v/2000862202001/

2. But it gets worse...

Most gas stations don't want to install new tanks just for E15. Instead, they're installing blender pumps, which mix the ethanol and gasoline together in the right proportion depending on which one you want. But there's a problem: if you pump E15 into your car, about a third of a gallon remains in the fueling hose when you're done. If someone comes along, switches to E10, and buys a single gallon for their lawnmower, they'll get a third of a gallon of E15 and two-thirds of a gallon of E10. That comes to about 11.7% ethanol, and that might be enough to set your lawnmower on fire.

So the EPA produced a new rule: if you sell E15, you have to require your customers to buy at least four gallons of gas regardless of what blend they're buying. That's a big enough purchase that the residual fuel in the hose is too small to matter. So let's count up the problems here:

Corn is the largest U.S. crop (70 million acres generates 130 bushels/acre). The U.S. produces 44% of the world's corn: Canada produces 1%. 6 million acres of corn is now used to generate approximately 1% of U.S. fuel requirements.

One gallon of ethanol is equivalent to .65 gallons of gasoline. It takes 22,000 Btu to create a gallon of gasoline, which has 120,000 Btu. It takes 98,000 Btu to make a gallon of ethanol, which contains 76,000 Btu.

E15 can destroy small engines. The EPA requires gas stations to post a warning sign, but we all know how much attention people pay to warning signs in gas stations. We're probably going to end up with a fair number of fried snowblowers and ATVs before this is all over.

People who buy gasoline for outdoor equipment usually only need a gallon or two. Ditto for motorcycles, many of which have gas tanks smaller than four gallons. So at gas stations that sell only E15/E10, these folks won't be able to fill up at all because they won't be able to meet the four-gallon minimum.

 

Interesting info, thanks. But, E15 is 15% ethanol and in the metro NY area, the 93 gas usually says "up to 10% ethanol," so I'm not sure how applicable the E15 scenario is.

Is there any evidence out there that the lower ethanol levels are are damaging, or are folks just theorizing?

 

The only damage of which I am aware is to mileage as alcohol added reduces mpg. Because pennsylvania believes emissions are reduced as ethanol is added pure gas is not available here

 

I don't think it's available here in the Dallas area as we don't meet our required environmental level. Fortunately I can get 93.

Chuck

 

It is my understanding from both the video and other sources that the corrosive chemical properties of ethanol on fuel lines and the fuel system particularly in older cars is the primary risk. So the higher the percentage of ethanol (E15 is 15% ethanol vs. E10 is only 10% ethanol) the higher the risk is a fuel system not designed for ethanol mixed fuel will corrode. As the news video states, 2012 and later cars are required to have a higher level of protection against ethanol in their fuel systems. The primary difference between those cars certified as FLEXFUEL (like Chevy Tahoes and Suburbans) and vehicles NOT certified as flexfuel is the fuel system being better protected against the more corrosive ethanol in high concentration like in E85 (85% ethanol) fuel.

 

Personally I wouldn't fill the 911 with Ethanol blended fuels, call me paranoid

As a matter of interest I just jumped on the US Shell website but couldnt actually find the octane rating of the Shell V-Power fuel. In OZ its 98 octane but couldnt find it for the US surely there are fuels higher than 93 octane available at the pump in the US? Either that or for some strange reason the octane ratings between the two countries are different, but in essence the same? ie 98 => 93 in US (strange to believe this though) I would have thought octane ratings (international standards?) are the same regardless of region.

As a matter of interest I also drive an Aussie built GM based V8 (coming to the US as the Chev SS I believe) and fill that with E85. Definitely more powerful than filling it with 91 E10 or 95 octane fuel. The biggest drawback is consumption is about 30% worse off.