I am blown as well. Did you do the mod before or after you installed your SC?I've got the SRT8 shorties and mid-pipes stepped down to an R/T sized Corsa exhaust. No problem on my end and it breathes a bit better, but I'm blown so don't know that I'm all that much help for you. My expectation is you won't feel much of a different but it'll sound a bit different. You're giving up a bit of back pressure so you may lose just a smidge down low and pick up a bit on the top end, but that's a guesstimate.