I have a custom bent 2.5 inch pipe catback exhaust with a Magnaflow muffler on my wrx with a catless uppipe and downpipe. A few days ago I finally had enough of the constant whining from my passengers about how loud my car is and got a Magnaflow resonator installed. The sound is still quite pronounced but it definately took the edge off. My question is, will it affect my performance? I thought I may have noticed a slight drop in power but my car always seems to have good and bad days. I took a look at it before it was put on and I could see right through it, there didn't seem to be any restriction (which makes me wonder how does it work?).

 

What a resonator is is a slightly larger pipe with fiberglass aka glass pack that muffles the edgy tones. The kind you have will be barely noticeable even on a dyno, 4-5 horsepower if you have an extremely restrictive one. Magnaflow is a high quality piece so it shouldn't be a worry. The resinators you have to worry about are the corkscrew ones that make your exhaust go through what looks like a corkscrew. . . Good luck, and now you might be able to hear what your friend in the back seat is talking about . . . . that is a good and maybe bad thing

Rush

 

A resinator basically takes out the sounds that you wouldn't want to hear, a muffler basically quiets them. For example, if you took the resinators off the 350Z, it will have high pitched metal-on-metal sound (very ugly sound). Depending on which resinators you have, the sound of the wrx exhaust will also change. Of course resinators quiets the exhaust tone a bit as it removes the unwanted frequencies, however, the best way to quiet an exhaust tone is to replace the muffler with a quieter one.

 

excuse the noob question but is there a difference b/w a resonator and a silencer? my catback has a hole on the end of the tailpipe where i am assuming a bolt on silencer would go. is this the same thing? assuming its not, would a silencer affect performance?

 

Resonators are generally in line with the exhaust flow are the same diameter as the exhaust pipe. They are designed to absorb the sound waves through a perforated insulation material. These tend to have no effect on performance. A silencer is more or less a plug the changes the diameter of the tail pipe forcing the sound ro reverbarate back into the muffler. IMO these have to cut performance. After all, you are restricting the flow at the tail pipe by reducing the dia.