what's Cat-back mean?

why do some exhausts have the muffler in the back vs the long narrow ones?(that need to have the evap relocated)

do they need to be welded? or is a bolt on with clamps ok?

thanks
Steve

 

cat back refers to replacing the entire system from the catalytic converter(s) all the way back to the tailpipe. in our case, most begin after the y-pipe which is directly downstream from the cats.

some simply replace the stock muffler with a new one, but keep it in the same location at the rear of the jeep, usually utilizing the stock exhaust hangers. others relocate the muffler to somewhere under the driver's seat, before the rear axle. this gives added clearance in the rear to prevent you from crushing the muffler in the stock location.

you can weld them in, or use clamps. clamps are definitely more DIY oriented, but i'd recommend using the band-type clamps if possible. welding is a bit more involved, more permanent (better be sure everything is PERFECT before final welding), and it can be tricky in some of the tighter areas. however, it'll usually yield a better, less leak-prone system (if done right)