Dual Exhaust for 360 in '67 Dart

Wow, great stuff, thank you everyone.

I think I'm using that Quiet Flow muffler on my slant 6 system now. I use Dutra Duals and have a custom made header down to single 2 1/2" collector. FYI, I had bad resonance/drone right under the driver seat. To fix that, I cut out a 3 ft straight section, welded a 3 ft SS perforated 2" O.D. tube inside it (using shims to center it in the bigger tube) and reinstalled. The resonance was gone! I've never used a box or J-tube, but will look into it. I like the internal resonator as it doesn't change the outer appearance of your exhaust system, and it's not bulky like a glass pack, no fitment issues. If I have resonance perhaps my internal resonator trick will work on the duals.

My slant is pretty quite at idle and really quiet when cruising. My slant exhaust actually sounds pretty good, on acceleration it sounds like a v8. But alas, although my slant runs really good, ~200 hp, I miss the extra juice of a v8. Looking forward to the 360 magnum project!