as stated above.
reason being i like my itr piping, but im afrid its too damn small in diameter. i heard that i can keep it, but i want to check. oh yeah...the piping leads to a tanabe axle back with same diameter piping;2.25

 

You can, but why would you want to do this? It's like starting to go to the gym and then start smoking at the same time.

 

you CAN but it will eat a butt load of power

perhaps look into the e-cutout