what should i do after i install my RE 4.5 and some 32's to get better MPG and HP. i was getting about 16-17 MPG stock. and i know that will go way down after i lift this beast. so what are some inexpencive ways to counter act the larger rubbers? throtle body spacer,exhaust, air intake......any other ideas. cause this is going to be my DD and i need that gas milage. thanks for the help