I had a friend who did the same thing. Admittedly, it was a Celica instead of a trans-am and probably benefited more from the procedure. Still, after he was done, he said that it was a lot more trouble than it was worth. It did reduce the amount of road noise in the car, but not enough to make it worth all the effort of installing the stuff.

The problem is that most modern cars are already noise proofed pretty well, and an extra layer of rubber won't change much.

I've always said that you get more value out of more powerful amps/speakers/subwoofers than you do out of dynamat.

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Tony Fabris