I have one. Nice deep note on idle, very masculine roar when you're stepping on it. Reving the car out in tunnels never once failed to make me smile. This isn't your high pitched fart can that comes standard on all second hand riced out civics.
The drone (~100hz) however is pretty bad as with most 'race' mufflers. At highway cruising speed around 3000 rpm it's the worst. You can still have a conversation with your passenger but will always be reminded of the fact that you pretty much have a straight pipe for a muffler. Luckily it wasn't that noticeable when the top is down... But hey, my top is more often up than down unfortunately.
Performance wise? 20 to 30 newly added horsepower to your ride, easy. Or that at least is what it sounds like. Put your car on a dyno and I'm sure you will see nil hp increase (you didnt really think an axleback change by itself would make any difference in power output did ya?). Treat this as a cosmetic mod only.
Loved mine when it was in my ND. But as much of a basshead I am, I now can no longer stand the highway drone and have recently uninstalled it. Maybe I'm getting too old for this. The stock muffler will suit me fine until I get a helmoltz/quarter-wave resonator welded onto my race pipe. I'm currently learning TIG welding just for this little project, so will definitely do it; and report back if I have success in improving it.
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