My project is getting closer, scheduled for the Muffler shop in two days trying to figure out what is best for tail pipe size, it has headers with 3" collectors with 3" cut outs right behind the collector, am thinking 3" from their to Mufflers, (mufflers are Raptor with 2 1/2 openings) and then 2 1/2 on out the back, is this ok, or should I scrap all the 2 1/2 stuff. Car is a 3200 lb. with a 30 over 440, 9.97 CR, with max wedge heads and intake with 750 carbs, and a RB .510 lift 242 dur. cam. any guesses on HP