Currently I'm running the duel, I've got new headers and took my cat out, and slapped two cheap (22$ each on Ebay) N1 cans on the back. The reason for the cheap mufflers is I've been trying to figure out should I have gone single pipe or keep it duel. And, anyone know what that square muffler thing is right below the rear seats, its next to a little can thing, I think its for keeping cabin noise down but the guy at the dealer ship said it was to reduce sound in general. I want to cut it out and put either pipe or a glass pack there.


TL;DR: Duel or single, which well make more HP - Whats the little square thing and little can thing on my exhaust for.

 

I've noticed a lot of kits have a little bit of bigger pipe around the same place, so I'm assuming its for cabin noise. Would it make more HP if I take it out? I'm looking to track race this accord once I get my skyline so I'm not worried about practicality

 

well physic state back press reduces HP. But the bigger pipe the less back press you have also you lose your lowend. I wouldn’t open your exhaust much more than stock if you don’t have any internal work done. That’s when you can really take advantage of your exhaust. IF you have just bolt on's you won’t see much more power over stock. MAYBE 5-7hp without a tune and MAYBE 8-10hp with a tune. Like I said be4 the cam upgrade will be your biggest power adder at this point until you start bumping up your C/R with pistons milling the head single layer head gasket (not sure if that a good idea on v6 engine...only seen b series and h22 guys do this)