What is different that allows engines to be FFV's

What makes the flex fuel vehicles different from the non-FFV ones? intake, computer timing and settings, spark or compression?

I heard that the 5.7 gets terrible mileage with ethanol anyway.

 

Fuel injection system is different, I don’t know if it’s different injectors or not but the system has to inject more fuel to make the same power

*and also more stuff I don’t know anything about*

 

The injectors are definitely different. My understanding is the FFV injectors can handle more volume. Some supercharger kits did not require new injectors if the Tundra was FFV.

 

100 post and OP is already gone.

 

Gone?

 

Beaned.

See this BST link.

 

Thanks,never knew that existed!

 

Moot point I guess since OP may never read this but all vehicles get lower fuel economy on E85 because it has less energy density than E10 or pure gasoline.

 

Engine controls mapping.
Depending on the regular injectors, the size of the FFV injectors may be a larger flow capacity.
Seals in fuel system are different to accomodate the alcohol.
Fuel sensors for different fuel.