Okay i now figured out that i have a volt muffler and wanted to know
1) where can i buy a silencer for this kind of muffler
2)what size is my outlet (refer to pics) cuz i forgot lol
3)what you think about volt
4)will getting this custom 2.5' catback w/resonator improve sound and performance and by how much on performance.
5)I keep hearing people say put 2.25' catback on car. Whats the difference between 2.25 and 2.5 why is it better for 2.25?

And yes i should have went with a catback when i first got it, but was new to the modifying thing and bought a muffler, but now i know and i'm getting a custom 2.5'nch w/resonator catback installed on my 02 civic later on today.

Also think #5 is an important question because i want to know before i go get it installed with 2.5, so if you could please answer #5 atleast. Thank You

Sorry about all the questions but just wanted to know.

pics:

 

The purpose of widening your exhaust is to reduce back-pressure. This increases the exitting velocity of the exhaust,
which is what you want. If you widen it too much then the exhaust wafts around an doesnt exit as fast. Basically you
want to reduce back-pressure but not sacrifice the exhaust velocity. From what i understand 2.25" is the nice happy
medium as far as width (for n/a applications).