The gains are there, mpg’s drop big time. Next to that “race gas” pump at that delta sonic they have 91 non ethonal. That has more bang than 93 w/ corn in it. True story: some Arctic Cat sno-mo guys back to back dyno’d a 800HO motor. It made like 6 more hp on the non ethanol fuel than on 93.
Someone we both know told me that Kwik Fill gas makes their gas at 93 octane then adds corn for NY etc. which happens to take the octane rating to 100.
Other companies make it 93 with the corn already added.
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I will have to google “RS7 E85 tune”.
E85 is 100-105 octane you’re saying they add enough E85 to bring 93 to 100 octane?
Yeah. That math seems iffy. 85% at 93 oct and 15% at 105 would only get you close to 95. Still an improvement over 93 though if true.
Right but the increased ethanol content would require a retune because you would need to be using more fuel…
The reason people use 100 unleaded octane race gas is stoich is the same you’re not using 30% more volume like you would with e85.
I don’t know what exactly they are doing to get the octane but the theory is that They already have 93 octane fuel but to sell it in NY etc they add 10% ethanol which also raises octane. (I don’t know the science or ingredients behind it, they may be using E85 though.)
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30% more?!?!? Seems silly.
Other than filling up more often, it makes a ton of sense from a performance standpoint. You use 30% more and it costs roughly 20% less than 93. The results compare pretty favorable to race gas and it is available at a decent number of gas stations.
30% more fuel for 100+ octane at $1.XX a gallon vs paying $8-9 for 100 octane?
Not even getting into the cooling properties of E85
^
I checked my dyno numbers and I make 55 hp and 61 tq more on E85 for similar cost per mile.
I did not know e85 was that cheap.
I found this on another forum…
"E85 is like race gas. Definitely high octane and some people feel that it actually makes more power than e.g. C16 race gas.
The problem with E85 setups is fueling. The engine needs about 30% more fuel than normal gas, which for high performance setups makes it difficult or not cost effective.
I remember when I had my built EVO, I was running double 255lbs Walbro fuel pumps and 1200cc injectors, They were good for race gas and up to 35-36 psi boost, but for E85 I would need 1600cc injectors at minimum and preferably ID2000s… Somewhere you win and somewhere you loose.
I can’t even imagine the cost or the difficulty to modify a DFI engine that in essence does not have injectors to run E85. I think this is the issue with the newer 911 turbos since they are DFI too."
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I do remember reading somewhere that almost every car can easily run on 50% ethanol but not 85%.
I ate a Corvette for lunch today.
very late to this post but hot damn dude… looked awesome in person at the parade
Thanks! Did you wave to me? 
I was going to buy the race gas mix from Summit when I noticed it said it was not o2 sensor safe. WTF? Does anyone have any insight on that?
Must be leaded.
I put 5 gallons of Delta-Sonic 100 octane in a can and drove until I ran out of gas tonight on some back ass country road.
After putting the 100 octane in the fuel tank and changing the tune to 100 mode, I did a couple of pulls in Mexico. After launching the car for the first time it started beeping, I thought something was wrong but then I realized that it was the speed alarm that was set at 100mph. It gets there like now! Maybe I should get it on the rollers while the go-go juice is in it.
Fun stuff.
You need unleaded race gas something like MS109 or 100 Octane from a pump at Delta.
If you can find a VP fuels dealer you can get cans of MS109
It did not say it contained lead but I was guessing it did contain lead. I used Delta-Sonic 100 octane.
WARNING RANT AHEAD…
Long story short; I purchased an item made in China and big surprise, it did not work. So I had to go to McKinley Mall to return it and when I traveled up McKinley Road I hit a pot hole and tacoed a wheel and pinched a sidewall! Summery: I HATE Chinese crap and even though I pay huge taxes in NY I still hit huge pot holes. FUUUUUUUUUUUUUUUUUUUUUUU!
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Beware of nasty pot hole near Five Guys Burgers.(Heading north)
I was JUST there… but then again I have quite a bit more sidewall on my truck than you do.