I use the regular 87 octane fuel but would it be better to use a higher level?? What do all of you use?

 

Shane hi first . I did a check on octane difference in my FX4. I ran the 87 then went to the 89 for two tanks the mileage was about .6 tenths higher which to me did not off set the 10 cents more per gallon. I'm still watching the superchips to see what programs will make a mileage gain.I get about 14.6 to 14.8 with 87 and 15.4 with the 89 . I tried not to change my driving habits for comparison.

 

factory recommends 87. Use 87. Anything higher is just running through your pipes unburnt. The sparkpoint of the higher octane is greater and alot of unburnt gas just goes right out ur pipe. This is why using higher octane allows u to increase spark. It certainly isnt hurting your engine by using the higher octane, but its not helping it either. Now if you have a programmer thats something different but on a stock truck your just wasting cash at the pump.

Dan