Thanks to everyone who actually answered my last question.

I have an 01 TL and wanted to install an intake and headers. Will installing headers cause a change in the sound of the engine? I know the intake will, but I wasn't sure if the headers would do the same.

Also...what is resonance with headers? I know, DUH? But I really don't understand what that is. I've read a ton of these threads and still don't have a good understanding of this term. Is it a sound that I'm listening for? A vibration?

Thanks again for those who help out!

 

Headers will not change the sound from your engine at all. You will not notice a difference in sound. An intake you will hear a big difference with. The resonance is caused from vibration from your headers/downpipe connected usually or the header to manifold connection. resonance occurs normally when the headers and not tight enough or they are not flush with the manifolds or downpipe. Resonance is not good, a little is not a big deal, but a loud vibrating hum is bad.

 

Resonance is any thing from a hum to a vibrating hum sound/drone and can become anoying at certain RPM's

 

Headers can and will change the sound of the engine, or more accurately, the sound of the exhaust note. The width and length of the pipes not only determine the peak power band, but they also affect the exhaust sound.

For instance, the stock exhaust manifolds are thick cast iron parts that are designed to keep it quiet. Changing to freer-flowing, thinner stainless steel pipes will not insulate sound as well, and you will notice it.

Resonance is caused by engine noise frequency. As I mentioned above, the length and width of the pipes affect engine sound, and at one point or another, the frequency of the exhaust gas exiting the engine and entering the headers match the width/length of the pipes, therefore resonating. With my limited knowledge, that's the best description I can come up with, but that's basically the jist of it. Like fsttyms1 said, it can get REAL annoying and in most cases, it is not fixable because it is due to the design of the headers, and due to the thinner pipe walls compared to the factory manifolds.

In any case, the power increase and the throatier exhaust note from the headers far outweigh the resonance problem (if you even have them... not all headers have this problem).

Have you ever stopped next to a loud motorcycle? And the exhaust sound resonated and vibrated throughout the cabin of your car? Well, that's kind of like what it is, except at a much lower level, of course, and only at a certain point of the RPM.

 

Resonance is a classic trademark of Alphawerks and megan racing headers

 

When I had my headers installed over a year ago with only a K&N filter I didn't hear a difference at all. Even when I added a CAI I didn't hear a change in my exhaust note, probably because at vtec all I can hear is the intake anyway. now with my catback installed there is no way to tell, but I still don't think there is a noticeable sound difference when headers are installed on our cars.

 

Like I always say, every car is different, even if they are the same model. Throw in an aftermarket product to the equation, and yeah...

I could definitely hear more of the exhaust sound from the engine bay after I installed mine. Everybody who knows my car commented on the same thing. And some of these guys have stayed up nights working on my car, just like I have on theirs, so they know my car. The exhaust sound definitely was more noticeable with the headers on.

 

Headers definitely changed my exhuast note... I have CT axelbacks...