Insulating barracuda fastback

I used Noico from Amazon. It is very similar to Dynamat, except the tin foil is a little thinner. It made of the same butyl stuff as dynamat.
Others have said not to use the roofing tar based stuff because it smells, but I have no experience with that. Buy it in as big is sheets as you can get, mine might have been 24x36 or something like that. I used aluminum furnace tape from Lowe’s for the seams, much cheaper.

I put the stuff under the door panels and about everywhere I could stick it. Really quieted down the car.