Hi,

I've just bought a 2011 JDM FIT Shuttle.

And am interested in adding some soundproofing. I've looked at a few posts. None seem to mention the thickness used.

Which make me wonder, IF there is a maximum thickness that can be fitted/ without stopping the carpet & panels from being re-installed.

Whilst I cannot afford dynamat, I've seen some potentially useful alternatives. Some thicker than others


thanks
david
getting FITter every day

 

There's a couple people on YouTube who've tried the same. Anything thicker than about two sheets of dynamat screws with how the car goes back together.

 

I did DIY sound deadening on my 2010 Fit Sport and can confirm that it's not difficult to go too far and make interior trim reinstallation difficult or impossible. I used Siless 80 mil (approx 2 mm) butyl automotive sound deadener sheets topped with Siless 157 mil (approx 4 mm) sound deadening closed cell foam.

I didn't completely cover the interior with the butyl sheets, but I overlapped the foam pieces slightly, so in any area the (mm) thickness of applied product ranged from approximately 8 - 10 mm, or 0.3 (5/16) - 0.4 (13/32) inch. Note that the closed cell foam is somewhat compressible, although that probably reduces sound deadening so might be counterproductive.

At this thickness, reinstalling some of the interior panels was difficult. It's been awhile, but I remember that the toughest panels to reinstall were the side panels (wheel well area) in the rear hatch along with the trim surrounding the rear hatch opening. Also, the small plastic covers for the front the front seat rails were super difficult to reinstall, and instead of breaking them I just left them out.

One tip that I figured out was to leave (or in my case re-cut) a small open area around the holes where plastic pins/clips from the trim insert and engage with the metal body panels. If you look at the back side of most of the trim pieces there is a decent amount of clearance, but the clips really have to engage directly with the metal surface. With that in mind, you could probably have more sound deadening thickness than I used as long as you leave clear spots for the clips to re-engage.

If you want to attempt that, I would recommend test fitting the trim as you add sound deadening. If you remove the clips you should be able to feel if the trim is still contacting the metal body panels (without constantly breaking clips). If it doesn't, you know you've gone too far.

Hope that makes sense.

 

Fabulous job! Do you feel it make a noticeable difference in everyday driving outside of stereo performance? I would be interested in doing it to quiet outside noise vs for improved stereo sound.

 

To be honest, when I'm driving I mostly listen to NPR or podcasts so I wasn't really worried about improving the stereo, although I do think there was a slight improvement. I was just trying to balance my small hatchback/decent fuel efficiency/no money lifestyle with a (sort of) quiet car.

For comparison, my previous car was a 2007 Toyota Yaris hatchback. Great car from a reliability and efficiency perspective, but it was loud around town and on the highway. On the interstate my wife and I didn't even bother trying to listen to the radio or talk. I always joked that we should get some rally car headsets so that we could communicate without shouting, and it certainly would have helped when she was trying to get me to take a turn or make an exit.

We owned the Yaris for about six years and were really ready for something quieter, but wanted to stay in a small hatchback. I bought the Fit from my brother, so I already knew that it was quieter than the Yaris. My hope was to improve further. Immediately after doing the sound deadening work I felt like it was a big improvement and was pretty happy for about two years... until last year when we bought a 2014 Nissan Leaf EV. In comparison (obviously not a fair comparison), my Fit now sounds like I'm driving a dump truck, especially on the *wonderfully smooth* roads of Massachusetts. My wife commutes in the Leaf and whenever she gets in the Fit she sort of furrows her brow and says "Wow, this thing is really loud!" But, I can hear her so it can't be all that loud, right?

So, I would say that with some serious DIY work you can make a Fit noticeably quieter inside, but you're not going to make it as quiet as a newer, more expensive, or more upscale car. For me, the beneFits of the hatchback and interior space outweigh the noise penalty vs owning a newer or more upscale small car.

 

Awesome, thanks for the insight! I just have a good amount of Dynamat and knockoff Dynamat from various projects that will cover at least the doors and hatch, I might get more for the floor if I get super bored. This is my son's daily so not sure if he even cares, but still fun to have projects to work on together

 

I see that you did a purrfect job. Did you do any in the engine bay soundproofing?

 

THANKS for the info about the clips. I'll bribe my Supervisor to make sure I can do a purrfect job.