I am about to order my '08 FX4, and I'm debating between the EFI and FFV versions of the 5.4L engine. Are there any differences between these engines that will alter the returns from my S&B or AF1 and RoushOR/Stock mods? Or are they essentially the same engine with a few superficial modifications from the factory to make it commpatible with gas/E85? I will most likely be running 100% gasoline tunes unless my E85 tune proves financially beneficial.

Any other advice? Thanks in advance!

 

Engines are the same except for some Ethanol capability Mods.......Mine is a FFV..........Still waiting for Ethanol to arrive here!.........

 

If it is still a no cost option, get it. You have better fuel system components to help with corrosion that the ethonol can create. No difference in performance between the two engines if you run gas. For dudge, I think the FFV option is $1200. Ford gives it to you for free... take it.

 

So-called "100% gasoline" is getting harder and harder to get. Most gasoline now is E10.