I can tell you one thing...Dynomax Super Turbo mufflers are great for a nice mellow sound, but flow like garbage. Get a straight through style muffler.
One of my old street and strip drag cars would pickup .9 ET (12.23 with them on and 11.39 removed) and 9+ MPH (109.4 versus 117.8 with them off with no other changes
) by removing the 2.5 inch pipes with the old Turbo muffs with 2.5 inch O.D. tailpipes that exited in front of the rear tires on my 1969 Dart GTS 440 powered
My Duster had a set of the cheaper crimp together Magnaflow 14x7x 3.0 inlet and outlet oval muffs straight through with perforate pipe, it ran 7.01 ET in the 1/8 mile with them on and 6.98 with them off
Those muffs were mounted behind the rear end between the 1/4 panels in rear sub frames. That really surprised me and impress me
I can't find them anywhere to buy them now
