just recently purchased an N1 apexi cat back exhaust and i was wonder since i've seen that most people take out the silencers in their mufflers, what is the actual purpose and does it affect performance. Ive heard that if taken out you can actually lose hp from lost back pressure? anybody got some answers to which is better in or out?

 

I think it does hurt performance a very little bit. I'm not sure if you can tell or not. Backpressure is a bad thing. The purpose of it is to make the exhaust quieter.