Do ya love yer sidepipes???

[Rick Parker]

I want to give a "High 5" to Rare Iron for the following comment, he hit the nail on the head

There's no sense spending THOUSANDS of dollars on a high HP motor only to have your mufflers rob you of 100+ HP (not to mention torque) in the power band.

This speaks volume along with what Duane said about pipe sizing and muffler design. The problem herein lies in the fact that many of you have increased the cubic inch displacement of your engines substantially, some by over 100 Cu In. yet you are still attempting to force it through a header and muffler sizing that was intended for a 427, and was not all that great on it. You must remember that header design an theory was only about 3 year old when these cars (427's) were on the road. If you look at the original collector design and if you understand exhaust theory somewhat you will realize there is severe turbulance in that design and there is no band aid that will make that design any better. Enter the "Merge Collector", read on some sites how effectively they are and how they assist in extraction of the exhaust gasses and you will soon see that it is not just the muffler that holds the key to what you are looking for.