Looking for some under carpet stuff. I saw Groucho's post on dynamat and looking on evilbay there are a few other options. Just wondering are the other two ok?? or just go with the dynamat and be done with it?? any thoughts or suggestions I'm looking at doing a couple of cars so will need 5 boxes of the 36 sq feet of dynamat . the others are cheaper but are they the same quality?
There is a Roofing product called Weatherwatch I think it's made by GAF, very similar to Dynamat. It is used on the bottom 3' of the roof instead of tarpaper under the shingles, most cities in cold weather climates require it by code. It comes in a 3foot wide roll,and is available at most building supply stores. I've never used it on a car for sound deadener but I have put it on Roofs.
Also a product out there called Koolmat I read some good things about on a Vette board. Not sure of its pricing, tho. www.koolmat.com
There's also a roll of roofing material called Stormgaurd Leak Barrier. The Weathergaurd & Stormgaurd would be ok on the floor only. I personally wouldn't trust anything but Dynamat under headliners, and use the other brands on verticle surfaces, inside quarters and doors, etc.
This might be of some interest to you.....several pages here. http://www.sounddeadenershowdown.com/which/
I used one of the stick-on tar roofing products in my '40 on the floor & even some side panels - made a big difference & much, much cheaper than dynamat. For the roof I used some very light foil-bubble stuff that I glued on. Do a search for soundproofing or something similar - plenty of discussion here.
Check this out, and support a HAMBer, that's how we roll - this is good stuff... http://www.jalopyjournal.com/forum/showthread.php?t=202951&highlight=sound
good friend of mine has done car audio and home theater professionally for years and he highly recommends fatmat, as dynamat is pretty overpriced. look for the 80-mil thick Rattle Trap Deadener by FatMat, they have a ton of different rolls and panels listed on ebay. in addition to a noise deadener it's a thermal barrier...not all sound deadeners are thermal barriers. the ones designated as thermal barriers typically have a metal backing and a much better adhesion.
Whatever you decide to use make sure it is non-flamable. Accidents happen, things catch on fire, being toasted ain't no fun.