I got the replacement muffler which is the generic oem one on my car because the other one broke off at the bpipe. I can notice a huge difference for some reason that my car doesn't take off like it used to. Does my muffler need to be broken in or something? And if it lags this much now how will me getting a ypipe get the exhaust out faster. Anyone else have this problem happen to them?

 

maybe the variable exhaust flap is broken so the exhaust is only getting out one outlet

 

how would i check to see if that was the case?

 

have someone give it gas while you hold your hand behind the muffler. at idle it will only come out of the right one (looking at the rear of the car) above 3K rpms (i think..might be 4K) it should come out of both