So I recently bought a 93 civic ex with the stock d16z6 in it. The previous owner put full intake on it, bigger intake manifold and throttle body and short ram, they welded a muffler onto the stock exhaust and its pretty quiet, I was going to keep it like that but I heard if I put header and catback on it will make it way quicker because of all the intake stuff, does anyone have an opinion or anything on this? I want to keep it as quiet as possible but I also want to improve hp.... Thank you.

 

header yes....full cat back is your choice though. bigger tubing means less back pressure, meaing no torque at lower RPMS and only higher RPM power...i would say get a 2.25" cat back, vibrant muffler, and a DC header

 

This is completely incorrect and has been documented a few times in this forum.

 

funny