[HWYSTR455]

Those charts don't tell the whole story, and are just guidelines. I actually see conflicting info from chart to chart as well.

As gasses cool, they contract, and it's an acceptable practice to use one step smaller tailpipes.

Another factor is bends, as in mandrel vs. compression. And the degree, number, and total distance. You can't compare header mufflers to an exhaust on a school bus.

I know folks that have gone through the trouble to go to 3.5 the whole way out the back, and there was no gain from 3", and the power level was there.

Going 3.5 over the rear and out the back takes some work on almost any body style. That's why many dump out the sides. That's not a good option for a street driven car, as most know.

I'm looking forward to the times of the OP since the tailpipe removal, very curious to see if there was a measurable improvement.

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