As for the cost of E85, it's currently around $1.49 here in my part of Indiana, while the cheapest top-tier premium is $2.59 (Mobil, 91 octane). E85 has about 27% less energy per gallon than E10, so even when you factor in the reduced fuel economy with E85 (assume 27% lower), E85 is about 40% less per gallon than premium. If you favor BP 93 octane for your C7 (as I do), that's currently $2.79 at my station, so now we are looking at almost a 50% lower "fuel economy corrected" price for 105 octane E85 versus premium.

The national average price for E85 is $1.65, while the national average price for premium gasoline is $2.69. Using these national average prices, and corrected for fuel economy, 105 octane E85 is only about 30% lower in price than 91-93 octane premium.

More power and less cost, what's not to love.

 

Ethanol has an octane of approx 105 burns slower more resistant to detonation. The impala could not utilize the octane. High compression NA motors will make a bit more power and boosted cars will see an even greater benefit with increased timing. It's all about timing. Ethanol has less power per unit of fuel so you actually burn more to make power hence less mileage. My other car a Mazdaspeed 3 running 24lbs of boost makes 386whp on e33 vs 330 on 24lbs. 91 octane. Timing.

 

I ran E85 and regular gas in my truck. I got 4 mpg less with E85. I was only getting 15 mpg with the regular gas. While E85 maybe cheaper at the pump it was offset by the mpg that I got. Also its gonna be kinda of difficult to sell this to most of us that live outside of the Tampa area due to the install and tune. Just sayin!!!!

 

I had a truck that was E85 certified. One of the issues was the caustic nature of E85. If the plumbing on the fuel system is not made for it, the E85 will eat into the hoses, make them soft and you will risk aspirating disintegrating hoses into the system. What's the status on the hoses for the Corvette?

 

Every car sold in the US today (and for some years back) will tolerate any ethanol blend fuel.