I prefer Corsa myself - it's a much more sophisticated approach than most makers - and very expensive to make. Corsa uses a series of Helmholtz resonators that "tap" off the main passage. Essentially - these are chambers of differing volumes and/or dead-end passages of different lengths. (In fact - this is sort of like the Bose radio bass resonators for those who have seen those.) The resonators essentially absorb frequencies in their tuned range. (This method is sometimes used in intake boxes as well, where a single resonator is tuned to take out what is perceived to be a "bad" sound component and/or reduce total intake noise.)
By doing this, Corsa mufflers have no baffles or other restrictions and flow straight through, unlike conventional mufflers.... this makes a big difference - and NO drone since one resonator is keyed to that frequency range to take it out.
They get a lot louder when the pedal goes down, since the resonators simply can't keep up.
That's another reason why the OEM's don't use this type of approach -they'd fail federal pass-by noise regulations.
No - I don't work for Corsa or know anyone there. But they are the only maker I've seen that uses a multi-resonator approach. I don't think Borla does this.
Oh - and I did pull the fuse on my system and thought it sounded very poor. Very, very boomy (at idle for one thing) and just not a pleasing, crisp sound. I grew up with 60's (pre-cat era) sound. I hate to say I'm very, very disappointed in the stock system.
Linear Mode
