Dynamat Extreme Questions

[xj220]

I'm about to install Dynamat in my car and had some questions I wanted cleared up before I began the process. First, I'm not going to do the full cover that everyone seems to do, instead I'm going to hit the main panels/open areas. With that, I don't have all the leaks in the car taken care of yet (cowl repair is the big one and too expensive for now) so I'm worried that if water does get in there it could somehow get trapped under the Dynamat and cause rust. Is that a concern, or is the adhesive good enough to seal between the Dynamat and floor panels assuming I match the contours?

Also, I have ACC mass-backed carpet and it looks pretty solid, but is there any chance water can get through it either? I want to make sure my bases are covered and don't cause future problems. Thanks for any help.

[TheJDMan]

IMO, ANY water in the floor is a BAD thing Dynamat or not. Rather than worrying about water getting under the mat I would be concentrating on keeping the water out in the first place.

[xj220]

I get that, but I can't afford to do the cowl repair right now so I have a vent cover. I'll keep it out of the rain until then anyways and it's garage kept so I'll minimize the moisture exposure of it.

[chuckd71]

Yeah fix that first, otherwise it'll be a mess if you decide to try to later. Those sound deadeners can leave a sticky residue sometimes. If you have leaks you can't seem to pinpoint you might consider taking a weekend to pull the interior and POR or rhinoline the interior metal. I did that to mine in case I ever leave the top down and it gets caught in the rain.

[xj220]

Here's what my floor pans look like right now. There's a little rust in the driver's area (it was wet when I pulled the carpet and old underlayment up) but its not showing on the outside so it hasn't gone through yet. I've got some plans to mitigate the leaks (cowl vent cover, garage kept, won't drive in the rain) but that's the best I can do now. A cowl repair for these Mustangs is several grand. Well out of my budget right now.

[mtconcha]

Don't apply dynomat or any form of sound deadening to anything you plan on fixing or replacing. It is an absolute nightmare to remove.

When you do apply it, wear mechanics gloves. Especially for that stuff you have. It will slice your hands and fingers to pieces.

I worked at a stereo shop for a few years, and they let me learn the hard way.

Also make sure to clean the surface well of dust and debris before applying, and use a handle roller to press the adhesive surface onto the metal for best results.

[rohrt]

Floors look solid.

To answer your question the dynomate should seal tight enough no water will be able to get under it and if your seams are tight no water should be able to get around it.

Like the others have said if you have any metal that needs repaired or replaced now is the time to do it.

[xj220]

Thanks for the help. I've searched all over different forums and think I have a good idea, but it's always nice to get some reinforcement.

[mc84_zz4]

I used a hand roller, screwdriver handles, and used regular scissors to trim it to size.
A wooden kitchen spoon, ended up being near perfect for little floor ripples.

Wear crappy pants, you will get little black goo spots stuck in them, same for shoes, watch out from stepping on carpet after.
WD40 will help cleanup on surfaces, garage floor, car door, etc.
Throw a towel on seats before sitting if you still have the same pants on...those little spots of goo can get everywhere.

I sealed the seams and edges with aluminum ducting tape, if you have significant work for wiring, stereo, etc before putting the carpet back in, it will help avoid cleanup of those tiny goo gremlins.
Good luck, you will really like the sound dampening, even a 30% surface use will reduce the noise.

[Jetfixr320]

http://www.summitracing.com/parts/sd...FQ8xaQodKd0PDQ

With that small amount of rust. Your cowl may not be beyond repairing/ patching with that kit from summit.
You install and bond from beneath the dash.