I personally don't think Sports Package will contribute to road noise much. Even with these wheels and tires, the 370Z is surprisingly smooth and plush without sacrificing the sporty feel and handling. It's quite an amazing difference compared to the 350Z.
Road noise is definitely worse in the 370Z compared to the 350Z and even the 300ZX (barely any road noise, but definitely lots of rattles and squeaks for its old age).
I'm definitely going to opt for some sort of sound deadening in some areas this summer starting with the rear fender well if I can get access to it.
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