I'm running 3" in the Coronet, 8 3/4" though. Less than 1/2" room on each side of the gas tank. But it all fits.You know, that's what I heard too. Even called TTi to inquire about running 3" through the mufflers and then going to 2.5" tailpipes. Both the owner as well as the tech guy told me that was a bad idea and not recommended. Although they would make it if I demanded, for an additional $150. Assured me I would have no issues with 3" all the way. I hope not.