Jon... he never said anything about going to a 4" pipe. You're twising this all up.
The guy just wants to pull his stock muffler and put a low restriction / better sounding piece in.
Is he an OSU student... then if so... yeah I know him. I've helped him install most of his mod's on his car.
I'm running Cobb Stg. 2 @ 18psi, ERZ catless Up, Cobb catted down, Perrin TMIC, AVO wastegate actuator, and muffler deletes.
Here is a vid I made when I got the first one fitted up.....
http://video.google.com/videoplay?docid=3371442942322151040&q=Muffler+delete&total=62&start=0&num=10&so=0&type=search&plindex=5
Finally thought I'd get around to posting up some photos of my DD for you guys. I hope ya like em.
http://i98.photobucket.com/albums/l263/smccorry/IMG_2267.jpg
http://i98.photobucket.com/albums/l263/smccorry/IMG_2268.jpg
http://i98.photobucket.com/albums/l263/smccorry/IMG_1682.jpg
http://i98.photobucket.com/albums/l263/smccorry/P1000290.jpg