I just finished installing FatMat sound deadening material just about every place in my trunk that i could. The entire floor, trunk lid (also filled with minimal expanding foam insulation), rear deck, and fenders. (i left the seat back alone so far).

My car sounds AWESOME. Bass is super clean and road noise has been cut dramatically.

But.... when low frequency long bass notes hit.... there is a vibration coming from the little flaps on that trunk vent on the drivers side trunk panel near the bumper.

What adverse effects would there be by closing that vent off? Or perhaps modifying it so it doesn't vibrate so badly.

Any thoughts on this?

-Andrew

 

Well, I need to do something about mine because my entire rear deck where the it meets the rear window flaps now...

 

Did you close off those vents? I'm getting pretty much zero vibration anywhere in the trunk of my car since i pretty much covered every surface except the seat back with FatMat www.fatmat.com . I may give it a shot closing those vents but it may cause other problems like too much pressure in the trunk.

I'm trying to think of a way to vent air into the passenger compartment from the trunk so there isn't so much pressure in it when the subs are rockin.

 

Those vents are there to release pressure when the car has a sudden change in internal pressure. They are called "rollover vents" and the main job is to prevent all the glass from shattering. A safety device of sorts.

 

Hmm.... for some reason i'd think you'd blow out your windows anyways in a roll over event....

Regardless.... the car would be considered totaled 99% of the time anyways if such an event occured.

 

You could cut like a vent throught the plastic part behind the armrest and go into the trunk...

 

I was thinking about going that route since the rear deck is not something i want to cut any holes in. I also want to retain my rear speakers for fill so taking them out isn't much of an option either.

When i get my front speakers replaced with Boston Acoustics Pro Series components, i'll unplug the rears to see if they're even worth keeping.

 

Any pics of your trunk?

 

The safety feature is there because when you close your door the flap opens so that you can close the doors. if you were to totally seal a car and try to open or close a door the pressure would make it very difficult, the car is by no means sealed from the factory so there would most likely be no adverse effects if you seal these off.

 

Since these two photos i've done the rear fenders inside the trunk, the rear quarter panels, rear deck, and all the doors.

I'm thinking about making a carpeted cover for the inside of the trunk lid.

 

got anymore pics? thinking of ordering some fatmat myself... how was install.

 

The install of the trunk was the hard part. It takes time, patience, and good measuring and cutting to get all the pieces to fit properly since there are so many curved surfaces. Looking back, I probably would have bought a different product called RAAMmat BXT. It supposedly performs slightly better but is a little more expensive though way cheaper than Dynamat Extreme.

I don't currently have any other photos of the setup. I'll shoot some shots of my door panels next week when my two sets of Boston Acoustics SL60 6.5" components arrive.

 

how good is all that matting anyway? is it really worth it?

 

If you've ever had a car sound deadened, you'd definitely say its worth it. road noise is greatly reduced, exhaust droning at certain speeds is eliminated, panels don't vibrate/rattle due to bass, and the cars doors just feel so much more solid when you shut them, etc.

Plus the new sound deadening materials are super light the old original dynamat used to weigh A LOT and their benefits for the weight were debatable. The new liners are very light and 50sq ft which can do most of the cars body panels only weighs 13 lbs. IIRC, old dynamat weighted probably 60lbs for the same amount of material.

 

you can pop out that whole vent pice! of take out the rubber flap. but it will got more dust in your trunk i notice