Since E85 has less energy density than gasoline, it stands to reason that we'd need bigger injectors to run it. It also has a higher effective octane rating than gasoline, which would mean that it could handle a little more timing and compression ratio than gasoline. I wonder: What would it take to make an engine that is optimized for E85? What is the "safe" compression ratio for E85 in a high-performance street application? Is the cam profile going to be any different? I'm not talking about stuff like ECM tune, injector size, fuel line fittings, fuel pumps or anything like that: I'm wondering what physical differences to the engine design are required to make the most of the benefits offered with E85 fuel. Most flex fuel engines are designed to run gasoline safely, and then they are adapted to run E85. What if we wanted to forego gasoline altogether and design the engine for exclusive use of E85? What parameters would we change ?

 

This post on turbomustangs has a TON of inromation in it.

http://www.theturboforums.com/smf/in...?topic=47094.0

 

I have to wonder: I've been intrigued with making an M85 intercooled turbocharged induction system for my 10.6:1 SBC, but would rather not throw away my forged Lunati pistons in order to drop the compression ratio. Since I have an all-forged 4340 bottom end in a line bored 4-bolt main block, and the pistons and cylinder heads are ceramic thermal barrier coated, wouldn't 10.6:1 be acceptable (perhaps even optimal) in a boosted M85 application?