Hi guys, my full setup will be, weapon r race headers/down pipe, to a 2" b pipe with a high flow 200cel cat welded in, then possibly a resonator here after, and finally all running to my current 2" axle back magnaflow straight through muffler, main thing I want to know, do I need a resonator? Is it just tonal or does it create needed back pressure? And if I do need one, will any universal 2" resonator do?

 

Resonators prevent that terrible droning sound, especially on the highway. Race cars do not run them because it adds weight. You won't be happy if you don't run one.

It does not prevent flow: http://www.roadraceengineering.com/p...f-louvered.jpg

 

It helps lower the terrible Honda angry bee sound, and doesn't restrict flow.

 

The WR "race" header eliminates the place of the stock cat, so you don't really need to put another high flow cat on your system. The resonator is more of a toning/flow item. If you want better non-restrictrive flow on your exhaust, then I suggest eliminating it. But be aware that your system will be louder in the long run.

 

I had an Accord for a while that didn't have a resonator and it was quite annoying and not any faster.