Surface Prep For Dynamat

[4packet]

I put DEI tunnel shield on the underside of the tunnel and slightly up the firewall. I've also got 6mm closed cell foam over the entire floor and behind the door panels. All gaps are closed off/sealed to the outside.

Generally everything is pretty pleasant inside. It takes a good 30min track session before the tunnel by my leg feels warm (not hot). Ideally I would reduce some of the noise from the engine (think it’s a mechanical noise as opposed to exhaust noise) and some of the clunk/whine from the poly mounted Cobra. The diff is the noisiest for me. I’ve avoided heavier options as I use the car on track also.

[RX7Driver4Life]

So this would be a superior product to dynamat extreme?
http://store.secondskinaudio.com/damplifier-pro-36-50-sq-feet-bulk-pack/

It looks like it is. I want to avoid the spray on kind and im not going for 100% coverage. Just replacing the oem stuff in the areas it was originally, then the spare tire area and the area from the bins back.

[65imp]

I would say all of those types are virtually the same.  Whatever you can get a deal on its what you should use.  Some are thicker butyl, some are thicker foil.  Avoid the tar/asphalt roofing tile $h!t.  You only need 25-30% coverage to get 95% effect.  This kind of product works to lessen the "clang" that sheer metal throws of when struck.  So use it in the large flat areas the most. 
Then throw some closed cell foam on top, it had much more of a "hushing" effect.

[RX7Driver4Life]

Thanks for the info. Gonna replace the oem stuff pretty much exactly as it was. Then gonna run a layer of closed cell foam over everything.

[just startn]

Lizard Skin. I have sprayed it on a few vehicles including my own. You can get in so many more places to drowned sound. IE: inside quarter panels ect. Previous sound deading was dynamat, this blows dynamat out of the water. I Would try to find someone with a compressor if I was in your shoes.

[RX7Driver4Life]

I decided to do a layer of second skin audio damplifier pro then a layer of closed cell foam on the floor board all the way to the trunk. I will be covering the trans tunnel with luxury liner from SS to control heat. I dont want to go through the mission of spraying the whole interior. I sprayed the whole floor with VHT epoxy paint and putting the SS damplifier over that.