So far for sound deadening I've done the following:

• Undercoated the bottom of my car & wheel wells with rubberized asphalt undercoating.
• Lined the center console with carpet padding.
• Stuffed carpet padding behind dash on the passenger side, and attached it all over the place under the dash.
• Put carpet padding in the spare tire well, then put the spare tire back.
• Stuffed the rear wheel wells (inside the car, behind the plastic) with batting material (the stuff you buy at Walmart to stuff a pillow).
• Removed the rear shock absorber nut/washer/rubber gasket and lubricated the area below with white lithium grease (to get rid of possible squeaks from rubber rubbing on the metal).
• Filled the hood with expanding foam, then put the factory insulation back on. (I haven't drove around with this yet - I'm letting it dry).
• Made a shock absorber header washer to put under the washers for the front shocks (made from 1/8" thick rubber, cut out 3" diameter, with a 1/2" hole drilled in the middle. Idea from this guy...

So, what's made the biggest difference?
The batting material in the rear fender wells (absorbed a TON of noise).
The rubber washer for the front shock absorbers (smoothed out the ride).

Anyone have any other ideas for sound deadening (besides the typical Dynamat answer... it's too expensive)?
Any ideas for ridding the doors of wind noise?

Thanks!

The Hood:


Rubber Gasket for shock absorbers:


Rubber Gasket installed:


Undercoating:

 

wow, u did pretty much everything one can think of. I've only done a couple of those things, but not even complete. I need more pillow stuffing.

Are you still on stock tires? getting quieter tires also help a ton! stock tires for the suck. Kumho ASX and General Exclaim UHP's are the 2 quietest ones i've tried. UHP's are ranked #1 on Tirerack in their category. I liked them so much, i'm using them on 3 cars, including replacing my new saleen's tires the 4th day i owned it. UHP's are also surprisingly cheap and GREAT performing for dry and wet conditions. Absolutely love'em!

 

No, I'm not on stock tires... My left-rear tire sustained a nail in the sidewall at around 50 miles (the first day). So I bought all new tires, since the stock tires do not last long.

UPDATE - the foam under the hood only gave marginal increases in noise reduction. The little improvement it did give is probably from the hood being heavier - and thus vibrating less in the wind (decreased metal-to-metal harmonics). I dunno

 

Thanks for the writeup.
One question: How did you get access to the inside of the rear wheel wells?

 

how about weight? did you notice that the car is heavier? MPG gone down?

 

that's what im wondering as well!

 

For the undercoating... just remove the plastic shrouding.

For the inside (of the car), I removed the plastic on the sides in the trunk area. An easy way is to remove the rear shock covers (which are inside the car), and the tail lightbulb access covers. Basically, I insulated between the metal wheel wells and the decorative plastic that you see when you open the trunk.

I'll take more pics tomorrow, and post them; pictures are worth a 1000 words, right?

 

Excellent question. I keep excellent track of my fuel economy, always writing down mileage (to the tenth of a mile), and fuel (to the thousandth of a gallon).

I used:

• 3 cans of undercoating (1.5 pounds each)... 4.5 lbs
• 1 bag of batting... 3 lbs
• Carpet Padding... 10 lbs
• 4 rubber gaskets (Shock absorber header rings)... 0.25 lbs

----------------------------------
Total Weight Added - 17.25 pounds

So did it affect fuel economy? No... not at all.

How much weight can a person add until it affects fuel economy? I wouldn't have a clue. But if you think about it - 17 pounds isn't much. Heck - If I eat a super sized meal at McDonald's (to include 1 or 2 drink refills), I just added more than 5 pounds to my stomach. I, personally, don't worry too much about weight. But I never carry anything in my car other than my iPod, spare tire/tools, and jumper cables.

 

For sound deadening look into RAAMmat or eDead from edesignaudio.com. I've used edead and its way cheaper than dynamat. I've also heard of people using roofing flashing.

 

I've read a lot about the roof flashing. Tempting as it is (and cheap)... I keep reading about it gooing up and stinking up the car.

I think I'll order something like eDead.

How many square feet of eDead do I need to do the Fit (floor, 4 doors, trunk)?

I know my wife is getting jealous of the progress; her Honda Civic is much louder than my Fit! That wasn't the case a few weeks ago.

 

Here are the pics of the wheel well area (there not of my car, but someone else's Fit who did the same thing)...

Batting placed behind turn signal area...


Batting placed between rear wheel wells and the decorative plastic...

 

so how would you rate doing the deadening in the rear fender walls? (1-10 1 being easy like installing a new shift knob and 10 tough as heck)

cause i think i might just do the rear fender wells and the front strut mod you mentioned.

 

Gloryhound -

RATING - 1, very easy

Just pop some plastic screws out, and stuff in the batting material. It's really that simple. Go to Wal*mart and buy a two 3 lb bags of the stuff... I believe I used 1.5 bags (4 pounds) between the two fenders. When it seemed like a section behind the plastic was stuffed, I would use a flat head screw driver to push the batting back further, and pack more in.

Also - I would recommend insulating under the center console. There's a lot of noise coming from there (at least in the MTs).

Let me know how it goes.

 

Thanks for the detailed instructions & pictures.
I will for sure perform the most contributive steps, including the hood: it may smoothened the noise from my TR1 Air Box. But I wonder if the undercoating will stick to the "grease based" anti-rust spray that I had done a year ago?

 

I wouldn't see why not! Asphalt sticks to everything... Before I joined the military I used to work at a plant that refined crude byproducts into asphalt. I would find asphalt 'dots' on my socks and underwear when I would change out of my coveralls. And that stuff would NEVER come out.

 

Thanks for the reply. Now I have tons of projects for next spring

 

I did some more sound deadening today. I pulled the rear bumper, closed off the rear fresh air vents, and undercoated over all the drain plugs and fresh air vents. I did a full write-up here (sorry, I don't want to re-type):

More Sound Deadening

Once I am *finally* done with all the sound deadening, I will put up a full DIY writeup here.

NEXT on the slate - more sound deadening for the hood. Also - here's a link on sound deadening from the University of Texas.

 

Check out these two threads on how much material to use.

https://www.fitfreak.net/forums/fit-...ighlight=edead

https://www.fitfreak.net/forums/fit-...ound+deadening

 

Cool - thanks for adding those to this topic!

BTW - I added foam to the hood of my wife's 98 Honda Civic tonight.
RESULTS - The hood is a LOT more heavy (the channels where I put it hold a lot of foam). Also - the sound is greatly reduced from the engine. Now, my wife and I can tell a lot of attention needs to be paid to the center console, where a lot of transmission noise is coming from.

 

This really works. I stuffed two bags of the pillow material in these locations and was amazed how much road noise was reduced. Took all of 15 minutes.