i am talking two pipes (duels). even a 500 hp v8 only needs something like 2.5"/side to breath adequte(sp?) amounts of air. single pipe is for pussies.
the bigger the pipe the more space, the less reverb of the sound, it makes it deeper. look at a diesel engine, with big exhaust you dont even have to run mufflers, but if you run small pipe you will need them.
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