[jramosGT]

I've owned a '93 TT RX-7 since Aug '92. As I've posted previously, it's my fun car while the GT is my "dog-hauler," if you'll excuse the term. I've got all the mods, but run a conservative 13 psi boost to my stock turbos, putting down 337 rear wheel hp.

On the exhaust question. because the rotary is such a loud car unmuffled, most of the highly modified RX-7s run downpipe, resonated midpipe or hi-flow cat, and a cat-back. Without any muffling, the sound is untenable; and a wide-open rotary sounds terrible.

On the RX-7s, from its stock 255 hp, a downpipe gets you about 20 hp, a midpipe another 10, and the cat-back 5 hp. If you run all 3, you need an aftermarket ECU to control boost and feed additional fuel, or the engine is toast.

A piston engine will produce different percentage changes as the rotary is known to be more constrained by intake and exhaust.