Po924S

So I bought some new carpet off a 1989 944. But while im changing my carpet, i'd like to quiet down my car. where and how do I install sound deadnening?

Yabo

Most sound deadening is sticky backed, so you just put it where you want, an stick it. it is thick enough that in some areas you might have to do something differnet with the carpet or not do sound deadening there.

544DRS

I just went through this. I'm not recommending this, necessarily, but this is what I did.

1. Everything came out of the car: seats, carpet, door panels...everything. I even took the dashboard out (but for other reasons).

2. Try to fix all the "issues" you have with your car while everything's out, if it makes it easier or cheaper to tackle. Water leaks, rust, holes in the floor, bad wiring, slow power windows...whatever.

3. Realize the differences in sound deadening materials available to you. Read this website:

http://www.sounddeadenershowdown.com/

It'll give you some things to think about.

4. Be wary about applying the asphalt-based stuff on places that'll get hot enough to make it sag or come off.

5. Consider other options too. I called 3M and found adhesives that could tolerate automobile interior heat and hold enough mass to the door's inner surfaces without coming off, using stuff (thick EPDM rubber) that dampens vibrations as well as (and a bit cheaper) than the Dynamat Extreme stuff.

6. If you can, drive your car with only the driver's seat installed, and everything else gone, so you can really hear where the noises are worst. Be sure to treat those areas. For my 944, the floor, trunk area, rear seat area, and doors were the places I needed to treat. Yep...most of the car!

7. Realize it takes some time and $$$ to do it right. After I did the "empty car drive" I realized that if I was going to use any sound deadening, I'd have to use a lot of it, or always worry about not doing it right. So I put three layers of FatMat on the floors, over the trunk area (don't cover the gas tank gauge square), rear seat, and the bottom of the two rear compartments and spare tire well. The same thickness of EPDM went on the inner door sides, rear speaker area, and rear compartment walls.

8. If you try to use carpet padding on top of the SD stuff, be careful it isn't too thick. I made that mistake, and my carpet fit horribly, my seats were hell to install, and I eventually had to take it all out. My original SD stuff, from Porsche, was all ruined by water leaks, so I tossed it. If you need to replace yours, at least save the old stuff to use as a template.

Good luck,

Nick

Po924S

WOW! That seems like alot of work. Maybe I should re-think my sound deadening idea, lol.

Mamooguy

First and foremost check the insulation under the shifter. I'd say that's a prime source of noise issues. If it's crumbling (as it probably is if it hasn't been worked on in 20+ years), replace it.

BeerBurner

I've put some sound deadening in my Miata and it was fairly easy to install. It helps to get a little roller because it makes it easier to get everything properly squished to the car.

All in all, I just went to the areas I wanted to install the deadening, removed whatever was in the way of the bare metal, cleaned/vacuumed the metal, test fitted the deadening and made necessary cuts, peeled off the backing and applied it like a giant sticker. It took me about 45 minutes to do the Miata's trunk, start to finish.

BB.

V2Rocket

is dynamat asphalt based?

544DRS

The "original" dynamat is asphalt-based. The extreme stuff isn't. That website I cited in my earlier post tells a bit about the more-common sound deadening stuff available locally or on eBay.

Nick

Toran

I replaced the insulation under the shifter with a big-ol-shaped peanut sponge used for car washing. It fixed the noise issue, plus the shifter doesn't have all the extra play anymore.

Fluidplay

+1 on the Dynamat...the stuff really helped make a quieter cabin.