Originally Posted by pinky_and_me
I have the flexfuel kit.
I think jb4 can be just as safe but it requires that you datalog every time you fill up with gas to make sure you car is running well. And also modify maps if you want to squeeze more power based on the ethanol content.
Because I don't have to do the above and I still get the safe power levels based on ethanol content I think the flexfuel kit is better.
No, the JB4 monitors timing advance and fuel trims and auto tunes itself when on E85. So you don't need to monitor anything. To run more than 50% E85 you normally also need the BMS flash which allows higher than OEM advance points and resolves the fuel trims issues.