Subaru Forester Owners Forum banner

1 - 8 of 8 Posts

·
Registered
2001 forester
Joined
·
146 Posts
Discussion Starter #1
Anyone got any reccomendations for a spray foam for sound insulation? I got some dynamat already but im also looking for a spray foam to fill in those cracks and larger spaces
 

·
Registered
1999 Forester S Turbo 5MT
Joined
·
1,960 Posts
Sea Scooby has an interesting and comprehensive thread on this. Following his example I have done the trunk on my 99 Foz. The entire base was done in Dynamat but I felt the benfits were not worth the 100 euro it cost so I have been using a product called Sound X from Fleabay which works out a lot cheaper. It's a bit more tricky to use but I think it should do the job as well as Dynamat. Sea Scooby recommended using hollow fibre to fill the cavities, the same stuffing you get in cheap pillows and cushions, and I believe you can get it over where you are in craft shops or the dreaded W...mart in cheap enough bulk bags. I couldn't find any here in Ireland so I bought half a dozen cheap pillows. The idea is to use your dampening stips to deaden the panels and then stuff the cavities with as much hollow fiber as possible. I did this a few days ago to the back door and the rear wings - huge hollow spaces generating noise like steel drums! I don't have a meter and I'm not interested in specifics because the rise in rate of decibels beyond about 85dB is not relative to the increase in noise levels that the human ear percieves, so I have done the driving/stereo test. The difference in internal noise in calm dry weather between 30mph and 75 mph is massively reduced after doing the back of the car. Using my USB stick on the stereo, my volume settings would have had to be adjusted at 50, 60, 70 and 80mph, starting at a setting of say 12 around town, I would have had it at 17/18 by the time I got to 70mph but, more importantly the bass and mid was distroyed. The last few days I have had the stereo at 8 to 10 around town only adjusting it to 12 at 70mph+. Also the quality of the music is back which is great because I am running an Alpine head, really good speakers and a sub. This was an excellent hifi system in my last car (Honda Accord 2.2 VTEC estate) but because the Forester is so noisy, their quality has been missing. Also I can now hear the engine and will have to do all four doors as well as the bulk head, but the decrease in the assault of noise from the back end of the car makes longer journeys a lot less tiring. So, long winded answer to your question on foam - hollow fibre, cheap and it works.
 

·
Registered
2010 Forester 5MT
Joined
·
61 Posts
I would steer clear of anything that will retain water. Cavities along exterior panels and especially in doors can have moisture and condensation - leading to mold.

I just deadened the doors on my 2010 forester. I used a combination of Hushmat adhesive panels from local shop (toronto) and ensolite (ordered from raamaudio). I was quite a job but the results are impressive - especially for midbass sound from door speakers (I also installed new stereo).

The ensolite can be rolled up and stuffed into cavities. I also draped several layers under the spare tire in trunk. As well, I hung 'curtains' of the ensolite behind door cards before re-attaching door cards. Rick at raamaudio even sells an aircraft grade spray adhesive that is perfect for attaching the ensolite to steel surfaces.

Hope this helps.
 

·
The Sub kit guy
2005 Forester X & XT VF39
Joined
·
13,008 Posts
The only areas that get water in them are the doors. The rear hatch and rear fenders stay totally dry. You can use a regular expanding foam (like what is used for homes), or use polyfiberfil (pillow stuffing) and fill up the empty panels. Stay foam is really messing but more dense, where as polyfil is cheap and easy to work with. I personally foamed areas I couldn't reach into, and I polyfilled all the big cavities like the rear fenders and hatch door.

This thread is about my SG, but the SF is pretty much the same so it still all applies.
http://www.subaruforester.org/vbulletin/f77/project-quiet-car-28591/
 

·
Registered
07 FXT sport
Joined
·
1,736 Posts
or use polyfiberfil (pillow stuffing) and fill up the empty panels. Stay foam is really messing but more dense, where as polyfil is cheap and easy to work with. I personally foamed areas I couldn't reach into, and I polyfilled all the big cavities like the rear fenders and hatch door. http://www.subaruforester.org/vbulletin/f77/project-quiet-car-28591/
What the properties of the polyfill that makes it attractive for this purpose besides it's price?? I'm looking at polyfill alternatives, that's why I'm asking.

dm
 

·
Registered
2004 Forester XT
Joined
·
96 Posts
I have read several threads regarding sound proofing and people have talked about using spray foams. The one thing I have not seen in any of the threads is any possible issues with the spray foam other than mess.

Does anyone know of any negatives, other than a possible mess, that would happen from using a spray foam?
 

·
Registered
1999 Forester S Turbo 5MT
Joined
·
1,960 Posts
I would steer clear of anything that will retain water. Cavities along exterior panels and especially in doors can have moisture and condensation - leading to mold.

I just deadened the side doors on my 2010 forester. I used a combination of Hushmat adhesive panels from local shop (toronto) and ensolite (ordered from raamaudio). I was quite a job but the results are impressive - especially for midbass sound from door speakers (I also installed new stereo).

The ensolite can be rolled up and stuffed into cavities. I also draped several layers under the spare tire in trunk. As well, I hung 'curtains' of the ensolite behind door cards before re-attaching door cards. Rick at raamaudio even sells an aircraft grade spray adhesive that is perfect for attaching the ensolite to steel surfaces.

Hope this helps.
I wouldn't recommend doing the doors with hollow fiber either because water gets in via the windows and drains out the bottom through drain holes, often sitting there for a while, but if your rear wings and tailgate are letting water in or retaining it, you have bigger problems to deal with before sound proofing/deadening. The EU Foz has the radio antenna incorporated into the passenger side rear cargo window so no ingress of water from electric ariels there either. The doors are a more complicated issue I think requiring re-mounting the speakers as well as damping the outer and inner skin with something like Dynamat?Sound X/Raamaudio products. The gap between the inner skin and the back of the door trim should be free from water because of the plastic membrane so I guess hollow fiber could be used in this space too. If however, money is not an issue, just Dynamat/Raamaudio the whole thing. Unfortunately a lot of the cool sound products mentioned aren't available here or are too costly to import. I just like Sea Scoobies practical approach for those of us who maybe don't have the money for the listed products (some members mentioned overall cost of $550+ for materials?)
 

·
Super Member
2010 Forester XT 4EAT
Joined
·
1,118 Posts
(I also installed new stereo).
Do you have any pics or your installation or at least of the new stereo? I would love to see what it looks like since I want to put a new stereo in my 10. Most cars here are 1st or 2nd gens and I want to see the 3rd gen with an aftermarket stereo since my imagination isn't that great!
 
1 - 8 of 8 Posts
Top