Just put the MBRP 5" turbo back straight pipe on my 07 CCSB LBZ........sounds good and all, but the air rushing sound at idle just isn't anywhere as loud as my 05 LLY w/4" straight turbo back was. Is this due to the diameter difference in the pipe, maybe? At idle, this LBZ is quite calm (for lack of a better word) sounding. Just curious.Thanks, Brad