New carpet and sound deadening project

[n2nsanity]

I didn't plan on this, but I've yet again started another project without completing the 15 others I was already working on. I started this because it's a convenient time since the seats are already out being re-skinned.

I started out installing the seat skins I bought last year, but then couldn't help but to clean up the nasty old rusty frames why they were out. With the seats out, I realized how nasty the carpet was, so I ordered new carpet. With the carpet out, I thought this would be a good time to do some sound deadening. I always hated how noisy the car is inside. Things like talking on the cell phone or listening to music would be so much better if I could get rid of some of the road noise in the cabin. I keep digging myself deeper and deeper, but this is where I'm at now. Hopefully I find a few tricks that will be useful to someone else.

So, seats and carpet out.
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The foot area for driver and passenger side have a hollow chamber. I think this is where half of the noise comes from. I decided to try some "Great Stuff" expanding foam in these chambers.
There are a bunch of holes in the top covered with this black tar-like material. Some of them were broken already, but I tapped a few others. I think a hole in each of the 4 corners and one in the middle would be enough to fill it up.
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After doing this, there was a night and day difference of the echo when you tap on the floor. I think this one trick (which is also the cheapest and easiest) will be more effective than anything else I do, lol.

There are also 2 other small chambers where the seat rails mount to the floor. Filled these up fairly easily and I could immediately tell a difference in the sound here as well.
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I used some Stinger Roadkill mat instead of Dynamat, but I think the results will be similar. I also read that partial coverage (about 25%) is usually all you need. I went with more like 50% to be on the safe side and cover the larger areas. By this time, most of the foam was dry so I shaved off the excess with a razor. I also ground down and primered/painted a few mild rusty spots while I was here.
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So from what I've done so far, the Stinger mat seems to reduce vibration by about 25%, but the expanding foam seems more like 75%.
I used up 1 can on just the driver side. 2 or 3 cans should be plenty.

*Mental note to make a video later comparing sound of untreated passenger side vs this foam filled driver side.