Senior Contributing Member
Join Date: Sep 2011
Location: Toronto Canada
Thanked 70 Times in 67 Posts
Neither an intake or cat back will change your gas mileage.
Sure it will cause you want to hear the exhaust and that will decrease your mileage .
After my Borla I was so happy I drove like I stole it the first week
07 SRT8 Silver Cam,PP heads&intake BT CC ,Borla S ,Eibach, Volant CAI Hid's all around Smooth and logoed moldings , Carbon Medic V2 ,Stillen's,Mopar Spoiler , TS led Rear fogs,Quad Projectors, 275/315 Dueller HP Sport ,Eibach's.Tuned By Diablo and CMR by OVERKILL, R1's StopTech's