Sound Reduction In Cabin

[Elanlover]

I recently did some Dynamatting on a new subwoofer install and bought plenty extar for a little experiment. I decided to try dynammting the trunk/boot to see what kind of impact it would have on sound levels in the cabin. Well, I've just done about 50% of the area and the sound has decreased noticeable! A significant difference in fact.

The fact that the entire bottom and side of the trunk are all thin fibreglass probably doesn't do much to make the car quieter I used the Dynamat Extreme which is lighter than the original Dynamat. Probably about 10 lbs. extra weight in total (all over the back wheels which is probably the best place to add any weight) and worth every ounce as far as i'm concerned. Something people striving to reduce cabin noise can think about.

[algirdas]

Dear Blair:

Thanks for the tip. I will be doing the PECO in the next few weekends and I am concerned about the increase in sound and the effect droning can have on longer trips. I was thinking of adding the Dynamat stuff to the trunk bulkhead between the trunk and the interior on the trunk side.

Sincerely,

Algirdas

[John_W]

Blair,
I'd be interested in a few more details of where and how you fixed the Dynamat. Does it need full coverage whithout any gaps, or are you just trying to deaden vibrations?

If you can be bothered, a picture or two would be nice.

John

[Elanlover]

..............I will be doing the PECO in the next few weekends and I am concerned about the increase in sound and the effect droning can have on longer trips. I was thinking of adding the Dynamat stuff to the trunk bulkhead between the trunk and the interior on the trunk side.

Hey Algirdas, this is EXACTLY what prompted me to Dynamat the trunk. I was just going to order enough to do the subwoofer I mounted in the tonneau then the exhaust imploded and I got that done. While i'm happy with the exhaust work, the noise level increased just enough to be a bit annoying on long trips. So, I ordered enough to do the trunk too.

At this stage, I've only Dynamatted about 80% of the trunk/boot floor beneath the carpet. I removed the spare tire and jack then Dynamatted most of what I could see. It made a noticeable difference for me. I plan on doing the trunk/tonneau wall, the rest of the trunk floor and as much of the rear wall where the rear lights are as I'm able. That should make even more of a difference.

I'd be interested in a few more details of where and how you fixed the Dynamat. Does it need full coverage whithout any gaps, or are you just trying to deaden vibrations?

If you can be bothered, a picture or two would be nice.

John

John, the Dynamat Extreme has a tacky backing. Just peel the paper and stick it to where ever you want (clean surface of course). You do need to press it doen into place to make sure it seals against the surface. They recommend their little roller tool but almost anything will work. Just roll or press it over the Dynamat and you're good as gold. Don't use your hands on the edges though. The product has an aluminum surface that, when cut to size, id VERY sharp. I have nasty little slices on 7 of my ten digits right now

Its best to cover as much as you can of course. You'll need to cut little pieces here and there to fit it in all the tight spots. You can cut them as small as you like to patch little spaces. I've got LOTS of gaps right now that I will go back and fill in later but even with 80% coverage on the trunk floor it a noticeable improvement.

I've got no pics at the present but, if you still need some help, I'll be glad to take some when I dive into the trunk again later this week. Remember, use the Dynamat Extreme product. Not any other of the Dynamat products inlcuding Dynamat original (which is heavier).

[Elanlover]

Just added a bit more Dynamat Extreme to the trunk/boot last night. I added some to the trunk floor over the wheels, the back of the trunk wall below the lights, a bit more to the "front" wall of the trunk against the tonneau and filled in a few gaps on the trunk floor I had left...................then I ran out

However, I detected slightly lower noise levels again on the way to work after doing this. I think its fair to say that the sound level is now the same or possibly even lower with the new exhaust and Dynamat than it was with the old, stock exhaust and no Dynamat.

[algirdas]

Dear Blair:

I was looking into this issue over the weekend. I think I am going to put Dynamat Extreme along the floor of the trunk (boot), the wall of the trunk (boot) between it and the cabin and the underside of the tray in the top (hood) storage (stowage) area.

Did you put it under your carpets in the cabin? You may want to consider that since (in my experience at least), that really quiets down the cabin. You would run it roughly from the speaker enclosures north to the floorboards and the area behind the pedals.

Right now with the stock exhaust and the Goodyear GS-D3s, the top down and the side windows up, the car is an absolute joy to drive. Very quiet and peaceful. I'm willing to give up a bit of that with the PECO but not all of it.

Sincerely,

Algirdas

[algirdas]

Dear Blair:

I was looking into this issue over the weekend. I think I am going to put Dynamat Extreme along the floor of the trunk (boot), the wall of the trunk (boot) between it and the cabin and the underside of the tray in the top (hood) storage (stowage) area.

Did you put it under your carpets in the cabin? You may want to consider that since (in my experience at least), that really quiets down the cabin. You would run it roughly from the speaker enclosures north to the floorboards and the area behind the pedals.

Right now with the stock exhaust and the Goodyear GS-D3s, the top down and the side windows up, the car is an absolute joy to drive. Very quiet and peaceful. I'm willing to give up a bit of that with the PECO but not all of it.

Sincerely,

Algirdas

[algirdas]

Dear Blair:

I was looking into this issue over the weekend. I think I am going to put Dynamat Extreme along the floor of the trunk (boot), the wall of the trunk (boot) between it and the cabin and the underside of the tray in the top (hood) storage (stowage) area.

Did you put it under your carpets in the cabin? You may want to consider that since (in my experience at least), that really quiets down the cabin. You would run it roughly from the speaker enclosures north to the floorboards and the area behind the pedals.

Right now with the stock exhaust and the Goodyear GS-D3s, the top down and the side windows up, the car is an absolute joy to drive. Very quiet and peaceful. I'm willing to give up a bit of that with the PECO but not all of it.

Sincerely,

Algirdas

[algirdas]

Dear All:

Don't quite know what all happened here with that triple post. I must have a bad case of the shakes. . .

Sincerely,

Algirdas

[Elanlover]

Algirdas, I did think about adding Dynamat to the floor.............that was, of course, after I'd already installed the new carpets there I believe that would make a huge difference though as well. I was mostly concerend about the increased noise from the new exhaust - thus the Dynamat in the trunk. However, if anyone wanted to reduce the "stock" noise level I'd suggest the floor and the front firewall. A lot of nopise comes into the cabin from the engine compartment.

[kenninuk]

Hi Algirdas. Just wondered if you managed to 100% complete your soundproofing project. Reducing internal 'boom' from the exhaust is at the top of my list for this winter so I would be interested in any other comments/advice you may have before I start.

Many thanks

Kenn

[algirdas]

Dear Kenniuk:

On my car, I have pretty much thrown in the towel. The PECO exhaust is so ridiculously quiet and coupled with Goodyear F1 tires, the car is, if anything, too quiet.

My fiancee and I drove back from the LOG in Aspen the entire way with the top down, carried on normal conversations and did not have to blast the radio to hear it.

On my fiancee's car, I will be installing Dynamat products since I am starting with a fresh bodyshell. But that project (Project Asta), will probably be starting only late next year or early the following year.

I hope this helps.

Sincerely,

Algirdas