2inches, yeah i got it online, I'm not gonna recommend you get it from driftspeed.com they were horrible.
i been reading reviews of people that own it, and ive only read good stuff.. "the quality of this exhaust is second to none! the car does seem to buzz/rattle a little bit with the silencer in, but wide open the thing just purrs with a deep roar. at idle its more quiet, but when you mash the throttle it just rips open. i'm very happy with my purchase" - HT member
Here are the specs:
* Full Cat-back System
* Full Stainless Steel
* Mandrel Bent piping<---- im really looking for this one!
* Bolt-on system
* Silencer included <--- ill prolly never use it.
* Street Legal <-- dont really care about that..
* 3 years warranty
* 60mm pipping 100mm tip <---66mm would be perfect.
you're not the only one who says is has a nice tone. ill for sure have to hear yours at the meet. i 'm in the market for exhaust, ive been in it for awhile, if i do decide to go with this i'll prolly get it off HT.