I've got a set of ITR pistons that I'm thinking of getting installed in my car, but noise is a concern. I like my car to be quiet when cruising normally. My car is decently quiet right now on the outside and I'm curious to know if the higher compression from the new pistons will make my car louder. I searched, but can't find any direct relation between the two. My car has the original cat with 2.25" piping and a resonator to quiet it down some. I bought with the exhaust it has on it. I think the guy at the shop said it's a like a cheapy turbo muffler. It makes the car look stock. Basically Im trying to figure out if the car will be louder or raspier at normal cruising speeds and under normal acceleration?

 

It wont be super loud, but you will notice it. I switched out my LS pistons (9.1/ 9.2 or so) with ITR's P73's and it had a better note at 5K plus. I have DC 4-2-1, high flow cat, and 2.5" to a Apexi N1. Thats one of the loudest exhaust anyways so I didnt really care. You should be fine.

 

added JDM ITRs and it is a bit louder... have on a apexi WS and while cruising it's pretty quiet. the engine drowns my exhuast note so the motor sounds really come out. you'll notice the difference but it won't be too loud.

 

My 11.5:1 LS/VTEC is way quieter than my original LS motor. Only time it isn't is in high RPMs when VTEC engages.