RWHEELS

I just installed the gt500 axleback exhaust on my 2011 gt, and its good, but could be a little bit louder, definitely the best for the money though. My question is for those who have this exhaust, does it get louder or change tone at all after break in? if so how much and after how long?

thanks
Rob

draxxus131

The materials within a modern muffler have no break in period, expect them to sound the same from day one of putting them on. 99.9% of exhausts offered by the factory are made to be 94.9 decibels or lower for noise compliance throughout the United States.

Nuke

Most exhaust systems that I've dealt with do tend to change tone (a tad deeper and louder) over time but to an "un-tuned" ear you may not notice the change. The time would depend on the mileage and composition of the exhaust but I'd say after roughly 500 - 1000 miles. The change (IF any) is so gradual that you'll barely notice it; similar to how slowly suspension components wear out.

Cockygt500

I have the Bassani cat backs on my Shelby and I think they have gotten louder since I fist got the car. My wife put my car is a car show and entered the loudest exhaust contest and my car hit a 127.7 DB with the short tube headers. Got any sound clips of your new exhaust?

Black Fire

I have the GT500's also and they do break in after 1000 miles or so but like nuke said it's only slightly noticeable. If you truly want louder just remove the resonators.

RWHEELS

thanks guys, I thought about the resonators, but have heard mixed reviews about the sound after taking them off, I'll check out some clips on youtube. Overall still a great exhaust, the closest to what I was looking for, and you cant beat the price

MustangVixenGT

I have an entire Stainless Works system on my Mustang. Which takes out the resonators and it's not quiet by any means. You hear the exhaust thumping from inside the car, it's hot though can feel the awesomeness!

Derf00

Can't comment about the dB rating since I don't have knowledge of the exact laws but on the Muffler sound (loudness) Yes, mufflers do get louder after several heat cycles and as they age.

Several expansion and contraction cycles will slightly reshape the chambers within the muffler(s), this will change the tone and pitch (typically making it louder). I've installed aftermarket exhaust before and that has always been the case.

Op, give it a couple weeks.

jRaskell

I've got around 7000 miles on my GT500 exhaust and it's really not mucher louder than when I first installed it. I plan on going to something louder in the spring, currently leaning towards Roush.

Cockygt500

Try shorty headers with it if you don't already have them. Could make it how you want it.