I completely removed mine, however I never took a base line b4 modding really. The trip home got me 33mpg going 65mph, and the 2nd fill up was like 35mpg after a couple of small mods. After the major stuff, I never really dipped under 40mpg except in winter.
Some day... I should finish my belly pan and figure out atleast a 1/2 boat tail for it lol. Would love to be hitting 50-60mpg
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