I have did some searches about dynamat and a few others. my question is half audio and half not. I just put my stereo in my car (no subs yet, this is a temporary system) And when you stand outside the car, its very loud, id like to cut down on this. ALSO i have a 80 series flowmaster muffler that is pretty loud inside the car, i was wondering, will dynamat help take car of the muffler and audio noise problem? Thanks

 

http://secondskinaudio.com/secondskin.html

secondskin makes products specifically for your problems at better prices than dynomat.

they make a "vinyl liner" which is good for keeping the muffler noise outside of your car.

As for as keeping the sound in they make a variety of products that should help keep the sound inside of you car, contact ANT hes very helpful, and will tell you exactly whats best for each of you problems.

 

Could that stuff be places on the firewall to keep engine noise out to? I dont mean like ticks or any bad engine noise lol.