I did the my "Gotts Mod" to my 07 F-150 5.4 Screw. I can tell that my throttle is more responsive, but it shows that my mpg are really low (8-11). I used to get 14-16. This is normal driving, not ripping on it. Is this gauge accurate now? Thanks for any help or advice!

 

Nothing about the Gott's Mod will hurt your fuel mileage ...
... except maybe that right foot.

 

How are you gauging your mileage, with and Edge/Gryphon or the truck's computer? If so, they aren't as accurate by any means when compared to using a calculator yourself.
I agree, it is probably that right foot but I don't know where you live and if you are running winter blend gas. Winter blend kills mileage alone by a few mpgs.

 

How many times have you gone WOT to feel the difference in throttle response?

 

time for the driver mod

 

I assume your going by your computer, which is by no means accurate.