rmodel65

dual exhaust actually increase your gas mileage by a little make the engine breath more efficiently that is if u can keep your foot out of the loud pedal instead of tryng to listen to the wonderful noises[8D]

rmodel65

and u really dont need 3" pipes a good 2.5 will be fine order a jegs catalog www.jegs.com or summitr racing www.summitracing.com and get some headers and and then take your car to the muffler shop also they have great buys on mufflers flowmaster,magnaflow, etc

jes72mustang

If you are looking at Headers, I for one will recommend the Dynomax Blackjack headers. I just installed a set on my 72 Grande coupe, 351C-2v FMX tranny, last night. When I was researching headers, I found all the manufacturers claimed their headers would not work with this engine trans combo, but could not give me a clear reason why or what the fitment issues were. I contacted Dynomax about my dilema, and they sent me a set of the Blackjacks, free. I am not saying they will do this for everyone, I got lucky and caught them on the right day. Anyway the only fitment issue I had was that I needed to dent the primary on the #8 cylender to clear the power steering gearbox. Other than that the fit and clearances are great. For the rest of the exhaust I would second what others said about using an exhaust shop.