ask as I ready to purchase my 3" exhaust I called Greg at SZ he cannot do 3" all the way back for a 2+2 without my car. I am in Mich / CA is a ways away. He said I would be ok with 3" to the catbacks and reduce to 2.5" and would be okay...the local ROUSH Racing guys say NO WAY !! Now I have to figure this out. I need 3" all the way back