Sound Advice

[ViperGMC]

Just thought I would relay my observations in regard to the Dynamat installation I just completed. I installed Corsa Track system and notice some additional vibrations/rattle after I took the car for a test ride. I also noticed some what of a hollow resonance that seemed to come from the area behind the roll bars. My idea was to install Dynamat material behind the seats to deaden the sound and vibrations a little. I removed the seats and pealed back the carpet to expose the metal panels. They are very thin and give off quite a tong when you thump them. I decided to see what was under the floor boards so I pulled up all the carpet, again very thin sheet metal. Indecently there was water under both passenger and drivers carpet. Another observation, the 3 screws that attach the center speaker box were just sitting there, not a single thread engaged. I decided to go ahead and use the Dynamat material through out the entire interior. I also covered the flat area behind the roll bar under the rear window. I put everything back together and went for a test drive. All of the vibrations/rattles were gone, the stereo sounded much better, the car felt more solid. The best way I can describe the impression is that all the rattle/noise, higher pitch resonance was transformed into a deep vibration that I could feel in my back, butt and thighs. I love the way the car sounds now from the inside and the outside. The stuff is very easy to work with, just cut the shape with scissors peel the back and stick. The job tool me about 8 hours, but I can’t think of a better way to spend an evening, next job, supercharger.

 

[KaiPL]

What year is your car?

When I bought my 6 point Team Tech belts, I had to cut through the carpet to get down to the anchor points for the bolts that hold the belts. I watched the guy on the team tech video easily cut down to the anchor points. However, when I tried to do it, I discovered a very thick layer of sound deadening material under the carpet. Several people have confirmed for me that 2004 Vipers have thicker sound deadening material than 2003 models.

 

[ViperGMC]

it's an 03. There is about 1/2" of that multicolored wool type insulation attached to the back side of about 80% of the carpet. The problem is that it is attached to the carpet not the metal. The Dynamat is stuck to the metal which changes the vibration dynamics of the matal panels. There was a tremendous difference in sound when I thumped the panels before and after the installation. I don't know about the 04

 

[LittleFish]

The material on my 03 was about 1/2 - 3/4 think foam rubber material with adhesive so tough that I almost could not peal it off. I put in the autoform rollbar and noticed what little sound protection in is the back. Where did you get the material?
Thanks, Dave

 

[SylvanSRT]

Question from the peanut gallery, how much was the total amount of added weight of the dynamat you ended up putting on the car, just curious?

 

[ViperGMC]

Peanut gallery, actually that is a good question. I used approx 45 sgft at .45lbs/sqft = 18 lbs worth. I thought the car felt a little slower, no wait I have lost 25 lbs since I got the car so maybe it was because I left he brake on. I am involved with general aviation and we are always concerned with weight, especially with a 1,100 lbs plane weight and balance is big. I always get a kick when a guy who has not seen his belt or feet in a decade talks to me about the weight of a vehicle. The best way to trim down a vehicle weight is stop eating so much. The supercharger is going to add more weight too, guess I will have to drop a few more lbs, no wait, I dropped 15 lbs with the exhaust change out, forget it, I can not keep track.

You can get the stuff at any car installer, Best buy has it, Crutchfield has it too. It is the “Xtreme” mat, there is also the Tac mat which is about a third the weight but is much thicker, .25 vs .06