octane effects power and engine temp?

[jdlmodelt]

Originally Posted by JAAY

Why would you put 87 in???

Its all the station had that I stopped at. They were the last station in the region that wasn't putting 10% ethanol in the gas. But, I think I would be better with 91 and 10% ethanol?

[jdlmodelt]

Originally Posted by jdlmodelt

Its all the station had that I stopped at. They were the last station in the region that wasn't putting 10% ethanol in the gas. But, I think I would be better with 91 and 10% ethanol?

I didn't notice, it must have happened recently, my wife said there is a new sticker that indicates 10% ethanol plus the inferior 87 octane. double whammy

[jdlmodelt]

my idle is rock solid

[Porsche9]

87 octane??? In a Porsche?? Ferdinand Porsche is rolling over in his grave.

[j.fro]

This is slightly off topic, but may be of interest. Occasionally I have access to non-ethanol 93 octane fuel. I keep track of my mpg and maintenance using an app on my iphone. I find that with the non-ethanol I get about 1-2 mpg better highway mileage, and that it improves another 1-2 mpg in the warmer months. Here's the skinny:
Summer, non-ethanol, 26-28 mpg
Summer, ethanol, 25-27 mpg
Winter, non-ethanol, 24-26 mpg
Winter ethanol, 23-25 mpg
This data was collected since mid May 2013 over 23,000 miles in a 1999 911 C4. I had noticed similar trends earlier in my 2000 986S.

[BYprodriver]

Originally Posted by j.fro

This is slightly off topic, but may be of interest. Occasionally I have access to non-ethanol 93 octane fuel. I keep track of my mpg and maintenance using an app on my iphone. I find that with the non-ethanol I get about 1-2 mpg better highway mileage, and that it improves another 1-2 mpg in the warmer months. Here's the skinny:
Summer, non-ethanol, 26-28 mpg
Summer, ethanol, 25-27 mpg
Winter, non-ethanol, 24-26 mpg
Winter ethanol, 23-25 mpg
This data was collected since mid May 2013 over 23,000 miles in a 1999 911 C4. I had noticed similar trends earlier in my 2000 986S.

I think it's directly on topic. Consumer reports observes a average 15% reduction in MPG with gasohol.

[JFP in PA]

Originally Posted by BYprodriver

I think it's directly on topic. Consumer reports observes a average 15% reduction in MPG with gasohol.

Brought to you by your Federal Nannies, along with less fuel stability, faster and higher levels of water contamination, and endless corrosion of expensive fuel system components......your tax dollars in action.

[CoBeerToad]

I keep track of my mpg and maintenance using an app on my iphone..

What's it called?

[j.fro]

The app is called Road Trip:
https://itunes.apple.com/us/app/road-trip-mpg-mileage-fuel/id298398207?mt=8

I think it's one of the best apps I've purchased.

[BYprodriver]

Originally Posted by jdlmodelt

Its all the station had that I stopped at. They were the last station in the region that wasn't putting 10% ethanol in the gas. But, I think I would be better with 91 and 10% ethanol?

This must be a high elevation location. High altitude reduces octane requirement since the lower oxygen content richens the air/fuel ratio.