Hi, in the next weeks (hopefully in 3-4 weeks), I will have to have the exhaust completely redone. I want it to be dual, as no header, it's a 318 2-bbl...for now This summer I will install a 4-bbl (unknow carb, with a Edelbrcok performer intake most probably). the future plan is to install a mild 360 (350-400hp)... So what size of exhaust should I go for, 2.25 or 2.5...won't be mandrel bent. Should I have one made for the 318, and then when the 360 is in, a new exhaust? What is the effect of a too large exhaust (i.e: dual 2.5 for a 318)?