Go to Hot Rod, They just covered all this in last month magazine. E85 has a high octane, and yes you need to raise the compression ratio to see the benefit. You can turbo charge or supercharge your motor. (most american auto companies now offer super and turbo chargers). you can also use a little NOS to really get up to speed. You need to advance your timing to run higher octane and higher compression. Its old school to hot rodders.

JIM

 

Yes, but the increased energy is a result of the engine modification, not a function of the fuel. (That is actually a "chicken vs. egg" arguement) You are more efficiently using the capability of the fuel, and the capability of the engine, but you are still using more of the fuel, which is less efficient in terms of fuel mileage. Also, when you raise the compression ratio, you will be using more fuel to maintain an acceptable air/fuel ratio since the increased compression can compress more fuel and air in a smaller space.

Only if the engine is tuned appropriately. The misconception is that higher octane produces more power, but octane is not a power adder. It is the resistance to detonation, or unwanted/unplanned ignition of a fuel charge. Higher compression means more heat in the combustion chamber and fuels with lower octanes are prone to igniting the fuel charge before the ignition event is supposed to occur.

Were you to take a non-ethanol fuel with the same octane rating, you would see nearly the same power gains. Where ethanol (or any alcohol for that matter) has the advantage is in charge density. Since more fuel moves through the engine, a cooling effect is generated and a denser charge is achieved. The cost of this is fuel economy.

Ethanol fuel can be a big advantage to "rodders" and more power can be made using it by tuning the engine for it, but it is important to know, or at least I think so, that the increased efficiency is not in terms of MPG.

 

Indeed it is "old school" which is what I find facinating about it! I also am amazed at the misconceptions of the fuel, since the technology is old, but that's what makes it interesting I guess.

FWIW, Car Craft also did a big E85 article a couple months back. It revolved around the new quickfuel carb and what gains could be realized as a result of the fuel. Neat stuff.

 

The factory flex fuel tunes are crappy and your fuel economy will drop 25% or so. If you go to a shop that specializes in tuning and E85 there have been guys that only see 15% drop.