[Sirrotica]

Over the years I've built a bunch of modified exhaust systems, the H pipe is what I've found takes away the annoying tones, and crackling. The crossover pipe needs to be smaller diameter than the exhaust pipes in my experience.

I've never had drone with an H pipe, but have had it with separate right, and left systems using generic turbo mufflers.

H pipe also adds to low end, and mid-range power in my experience.

From the mangled header test that was done on the dyno that showed virtually no difference, I fail to see how a dent, of flat spot in a tail pipe is going to significantly affect a street exhaust system on the butt dyno.

Tail pipes also eliminate the resonance off of the trunk sheet metal that turn downs at the rear axle seem to cause.