sorry, but can somebody explain the difference between an axleback system (comptech) and a catback system (apexi ws2)?

 

no difference. just designs of exhausts. plus comptech makes both cat and axleback.

axleback is what it is, from the axle back.
catback = from the cat, to the back.

 

which gives more power and sounds closer to a g35 exhaust?

 

you removing the midmufflers = g35 sound + i think it sounds nicer.

if you're aiming for the g35 sounds, just get rid of both midmufflers.

getting a new exhaust will make the sound totally different.

 

will it pass inspection? are they there for any reason anyway?

 

they're there to quiet down your car. and it will pass inspection with flying colors. anything after the cat is fair game. just as long as the cat is there.

 

https://acurazine.com/forums/showthread.php?t=180170

 

DO NOT REMOVE your first/front resonator! ..only remove the mid resonator. Removing both will give you too much of a throtty/ricey sound. I have my mid-resonator removed w/Comptech Axlebacks and it gives it a nice, deep tone.

 

Axleback = only mufflers

Catback = new piping from catalytic converter to mufflers + mufflers

 

^^