just bought my first cobra and i love it ,i can't wait to drive it every day. I work for Ford and needed a daily driver.It has long tube bbks,h,and american thunders. Undersize pullies. I have to drive 80 miles a day.. some one suggested 373s ,what will that do to the gas milage..and what else can I do to it that will only effect the gas if I get on it...which I love to do, should I lower it and how much and with what ?