The best replacement for flex fuel is ecoboost.

The best alternatives to flex fuel are rated as following:
★★★★★  ecoboost
★  non flex fuel
★  eco boost

Your alternative for flex fuel is not listed? Suggest!
Speaking about flex fuel, one probably shouldn't forget about regular gas.

Other search terms related to flex fuel and their ratings are:
★★★★★ regular gas
You have in mind a companion for flex fuel and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of flex fuel in all years. Click on graph for more.
flex fuel
ecoboost
non flex fuel