Originally Posted by Shmoo

The muffler alone won't really have much of an effect on the flow. The piping diameter before the muffler is ultimately the difference between a turbocharged car and an N/A car. If you plan on just putting the muffler on, it will be good for noise but not much in the HP department. Turbo does quiet the exhaust, so I would be curious as to how the Evo muffler would sound on an N/A car since the Evo is loud to begin with.