Not sure where this topic should be, but here it goes..

Do E85 tuned engines also run premium, regular, and unleaded gasoline?

If so, does the gas milage increase when runing the 3 other types of gas other than E85?

 

I heard that making an engine E85 capable has as much to do with solvent-proofing the fuel system as tuning the engine to run the different fuel. I think typical flex-fuel type cars run best on gasoline and 'get by' on ethanol, and they get better fuel economy on gas than on E85. Engines designed specifically for ethanol will be higher compression and won't run well on gas, particularly low octane gas.

I bet a lot has to do with how the engineer designed the engine (i.e. with what compression) and whether the ECU can respond well to the type of fuel that is present.

 

Thanks for the imput

 

If an engine is tuned for E85, it would run horribly rich with normal gasoline. You can only run E85 in an engine tuned for E85 unless you have an adaptive fuel management system that can determine the ethanol content of the fuel.

 

That makes a lot of sense.

Someone else told me otherwise, but I had to make sure

Thanks