96 Corvette Flowmaster 40 muffler noise inside car.

Just install some sound deadener. That should help to reduce or eliminate unwanted noise.

Thank you for your reply. Someone I work with said try dynamat what they use for installing car sound systems, so I did and it did not work noise still there. Is there some other sound deadner you know would work better. Thanks again.

Where did you put it? The trunk will need to be completely lined as well as the floor and sides of the interior.

I did the whole trunk area and behind the seats where the noise was mainly coming from, but not the doors or floor boards. I guess thats my next step then. Thanks for you help.

The fiberglass really doesn't help to reduce the noise so you got to use a good bit of it.

Dynamat will silence a lot but not all of the noise, especially if it's due to a resonance.

Resonance is caused by low frequency vibration and dynamat will stop vibration (road noise and etc.) so if used correctly it will get rid of it.

Thank you for all your help, I will try what you suggested and hope for the best. I have to order this stuff no-one sells it locally since circuit city went out of business. The only other option would be to go with a $1400.00 Corsa exhaust system which is supposed eliminate the noise, so I have been told by others such as the shop that put the flowmaster 40's on my car or go back to the stock mufflers. I just received a phone call from a friend telling me that Zeibart the people that do undercoating also does a spray on sound barrier which is a product 4 times heavier then undercoating and is supposed to quiet things down. I will have to call them a hear how expensive this is. I will let you know if you like, I will try to contact them sometime this week when I get home before they close. Once again thanks for your help.

Thank you Joe.

You could always try wrapping the muffler itself in heat wrap or replacing the exhaust hangers if they are hardened.