=========================================================== **** Bounces like rubber! Shatters like ceramic! **** Discover Crazy Aaron's Thinking Putty in grown up handfuls. It's the creativity unleashing, mood enhancing desk toy! caab5n2b7yoMza/ Crazy Aaron Enterprises =========================================================== I think the original factory High Performace single exhaust used a 2 1/2" pipe. That system was one of the most efficient & best sounding factory exhausts ever made, in my opinion. That '65 - '67 exhaust looks cool too, with that resonator and tip assembly at the end of the Hi-PO Darts and Barracudas. You may want to consider that approach. Moreover, I read that over exhausting (too big of an exhaust system) causes lost horsepower. There probably is a formula based on amount of air IN as to sizing exhaust pipes for amount of air OUT that someone may know. Gary H. pablo radic wrote: > > Hi. My next project in my 65 Dart GT will be the dual exhaust system. > I'm > trying to decide what pipe diameter to used 2.5 inch or 3 inch???. > I have read that is lot of problem space to fit a exhaust manifold > there, > but I will try a home made system,....we will see. Maybe I should have > to > change my power steering unit by manual??? > thanks =========================================================== **** Bounces like rubber! Shatters like ceramic! **** Discover Crazy Aaron's Thinking Putty in grown up handfuls. It's the creativity unleashing, mood enhancing desk toy! caab4CEb7yoMzf/ Crazy Aaron Enterprises =========================================================== ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html. b7yoMz.