I really cannot say how much you will gain horsepower wise. Raising compression to 12-13:1 will help alot with e-85. The jet area (not jet size, but orifice hole's area) will need to be changed to 147% as a ballpark baseline. Fuel not nearly as corrosive as they say, but worth mentioning.
I have a small block Camaro that went 11.67 at 116 last year on race gas with 11.5:1 compression. I increased compression to 13:1 and ran E-85 with a looser converter and on the very second pass ran a 10.90 at 125 mph! :shock:
Use big pumps and reguators, because you'll need the extra volume of fuel as well. Make sure your tank/cell is sparkling clean before adding E-85.
Run the engine hotter than on race gas. I went from a 160 thermostat to a 190 and found the engine was snappier/smoother.
We all know there are performance benefits on E-85, but what about cost? Well, let me put it like this...
Race gas times 100%= 8.00 per gallon. :evil:
E85 times 147% volume at 2.50 per gallon=less than $3.75! :wink:
Even if it were possible to burn 3x as much E-85 compared to race fuel it would only cost $7.50...that's still cheaper than race gas!!! Not to mention the fact that you can
drive down to the gas station and fill 'er up!
Hope this helps!