i was going to post this in the 4 banger section, but this will get more views and hopefully more responses here. i drive an 03 i4 5spd sedan and im looking into the possibility of going with a dual exhaust (IMO makes the rear look more symetrical). i read in the 4 banger section that it is possible to use an aftermarket cat-back for the v6 on the i4 with little modification, but then i got thinking that the piping is probally a little too large and i might run itno other unforseen problems. so my question is, is it possible to utilize an aftermarket v6 cat-back to get that dual look, or will i need to go custom? also, if i go custom, what size piping should i go with? im thinking 2.0 or 2.25 but im not sure. any help would be really appreciated! thanks!