[quote=Bmwnsxr;11183596]Yea It was probably 40 degree. Will that make a difference?[/QUOTE
the mod basically makes your car use both exhaust pipes at start up instead of closing one. So from a cold start your car will sound louder but in general it doesn't really make a big sound difference while driving when the car is warmed up. It isn't a very big difference but its there.