Any performance shop should be able to tune on e85. If I am not mistaken, e85 is on the same level as 106 octane. Yes, your gas mileage will be worse. But, you will be saving at the pump so you will come out even or save some money. With e85, you can run more boost with out detonation or higher compression. You need bigger injectors I believe than 440 due to the fuel flow. Your 255 should be alright. I would go with different fuel lines because e85 is denser than regular pump gas...