It's slightly louder than stock but I have an M6 with all 4 CATS off and all mufflers removed running straight pipes so a little noise doesn't bother me. Yes, the computer gets sent in to have it reprogrammed.

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Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out and loudly proclaiming: "WOW! WHAT A RIDE!!"

2007 M6
2018 Chevy 2500HD Diesel Alaskan Edition
2011 X5 35d
1972 Chevy K20 4X4
1972 Ford F-600
1959 Chevy Viking 60 Dump Truck
2015 CanAm Outlander XT 1000