I am having my back pad recovered this winter. While it is out, I am considering soundproofing the firewall.

One of my friends used Dynamat on his 67 GTO's floorboard when he restored it and swears by it.

Does anyone have thoughts or am I wasting my time and money?

http://www.amazon.com/Dynamat-10435-Xtreme...f=pd_sim_auto_3

I went to Home Depot and bought their brand of gooey tar, silver backed stuff. Put it on the backside of my back pad. About $14.00 per roll (6" X 25').

We use it.

You can save some money and get fatmat.

We have DynoMat in one car and FatMat in the other and we cant tell any difference...

I used Dynamat through-out the interior. With the uphosltry installed driving down the road is very quiet.

Getting ready to spray my lizardskin soon. Both the sound and heat types. Have a look online. Jegs has it in 2 gal for pretty cheap.

Is that just used on the inside? What is the best thing to use on the engine compartment side, rather than the old original thaw falling off?

I used dynamic on my doors hoping to help my anemic stereo system, it helped a little, but for the $$$ I should have built a bass box in the console. Probably would have helped more to do the floors and firewall as well...

Following this thread closely, as I intend to replace my factory piece on the engine side as well. I saw this on ebay:

http://www.ebay.com/itm/Porsche-Ultimate-E...=item43abd1ebc1

http://www.914world.com/bbs2/index.php?sho...;hl=second+skin

Not sure if your avatar pic is Soccer, Rugby or Aussie Footie - but funny as hell Eric!
... it gives POA a who new meaning!

Hijack - or side-track over!

I used brown bread on my VW bus, I think it was $60 for a 100' roll
works good, but it's no good inside the engine bay.

Slits Got Fired !!!!! Eric now has new people !

Jack

I used Dynamat throughout the interior (page 13 in my signature link). I did not really compare with fatmat but I am very happy with the results. Not sure about the weight difference but Dynamat is heavy as hell. I have a 3.2 so weight doesn't mean as much as in a 2.0. It is very easy to install, the noise dampening is fantastic.

I put Dynamat on the back of the firewall on the inside. Because of the glass window, you are not going to get a lot of reduced engine noise no matter what you do.

Lizard skin can be used in layers for inside and outside. Then you can paint it.

Dynamat is best at damping out resonating panels and not really blocking sound (although it will do some of that). The best thing to use to block sound is Mass Loaded Vinyl (MLV), preferably one that is foam backed (you put the foam side towards the firewall so the MLV is 'floating' and doesn't resonate with the firewall). Many people recommend a combination of dynamat (or any of the cheaper knock-offs) covering a 1/4 of the area of the firewall (or any other panel) to kill resonance with a closed-cell foam MLV to block noise. The other trick with the MLV is to make sure you completely cover the firewall...any gaps really let the sound in.

I haven't done this to my 914, but I followed this strategy for my Elise and it made a huge difference...the car is actually pleasant to commute in.

I appreciate everyone's input on this topic. There is a wealth of knowledge out there in 914World! Thank you so much and have a wonderful Christmas.

Terry

For >15 years, I have been hauling around a roll of sticky back, architectural , acoustic rubber (i think neoprene), So...

I just did this:

Layout


Rolled on


Trim alignment & drill


carpet glued to rubber


I havent had an engine behind it running yet, but well see.

Stu

Zach & I have used RamMat. It now comes in square sheets instead of a roll. They also sell an acoustic foam. I used both.