FWIW, I think the CCF is the stuff that will really affect dB readings. I borrowed a dB reader and the difference between my before and after readings was statistically insignificant with just the vibration dampener installed in my hatch. Even the difference between my before readings with the hatch completely bare and after with the Onyx installed and the spare tire and all panels put back in the hatch was very minimal.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |