PDA

View Full Version : Dynamat?



FordNut
05-07-2009, 09:15 PM
Sound related question, where are the key places for adding dynamat to reduce exhaust noise and enhance the sound system's performance?

I can hardly touch the gas pedal without the wife starting her yak-yak about the noise.

Bluerauder
05-08-2009, 03:50 AM
Sound related question, where are the key places for adding dynamat to reduce exhaust noise and enhance the sound system's performance?

I can hardly touch the gas pedal without the wife starting her yak-yak about the noise.
I would think that a 3 inch strip from ear-to-ear would significantly reduce the irritating noise -- a strip of duct tape might do the job just as well. :rofl:

W4LTD
05-08-2009, 04:00 AM
I would think that a 3 inch strip from ear-to-ear would significantly reduce the irritating noise -- a strip of duct tape might do the job just as well. :rofl:

http://images.cabelas.com/is/image/cabelas/s7_226002_imageset_01?$main-Large$

FordNut
05-08-2009, 04:35 AM
I would think that a 3 inch strip from ear-to-ear would significantly reduce the irritating noise -- a strip of duct tape might do the job just as well. :rofl:

Way too expensive. Been thru divorce a couple of times already.

burt ragio
05-08-2009, 05:00 AM
I put Dynamat in my car. Applied to four doors rear deck lid behind the back seat cushion seperating the trunk. It helped a little yes just a little. I plan on stripping the interior & doing the entire floor & around the wheel wells. As a result I may get half a mile less per gal. but it is worth it.

Pops
05-08-2009, 05:42 AM
I put Dynamat in my car. Applied to four doors rear deck lid behind the back seat cushion seperating the trunk. It helped a little yes just a little. I plan on stripping the interior & doing the entire floor & around the wheel wells. As a result I may get half a mile less per gal. but it is worth it.

As Burt says is a good way!:)

Glenn
05-08-2009, 05:48 AM
Brian:

The only thing that will resolve the issue is to put the OEM mufflers back on the MM. With your current 680 HP you will not notice any huge difference in performance and the sound will be significantly reduced. A second suggestion is to remove the delete tips and replace with OEM ones. But, nothing will reduce the noise like the OEM mufflers.

Glenn Ford :burnout:

O's Fan Rich
05-08-2009, 05:54 AM
I did the whole floor, the doors, the trunk divide, the rear shelf, the trunk shelf.
It worked great. Car is really quiet inside.
But did not use "Dynamat" .
http://www.motorcitymarauders.com/forums/showthread.php?t=6378&highlight=fatmat

ImpalaSlayer
05-08-2009, 06:08 AM
I did the whole floor, the doors, the trunk divide, the rear shelf, the trunk shelf.
It worked great. Car is really quiet inside.
But did not use "Dynamat" .
http://www.motorcitymarauders.com/forums/showthread.php?t=6378&highlight=fatmat

no your wrong it didnt help, just ask Glenn

ctrlraven
05-08-2009, 06:21 AM
I put Dynamat in my car. Applied to four doors rear deck lid behind the back seat cushion seperating the trunk. It helped a little yes just a little. I plan on stripping the interior & doing the entire floor & around the wheel wells. As a result I may get half a mile less per gal. but it is worth it.
That's what I would do also, though doing the trunk itself will help the biggest to eliminate the noise as it channels into the trunk and comes right through the cushion foam. Seal the trunk off from the cabin and some of the noise will go away. That's doing the rear deck lid and separator behind the rear seat cushion. Probably wouldn't hurt to do the rear floor also since the mufflers are pretty much right underneath there.

Needless to say you want to really quiet the beast down, remove your interior and lay dynamat extreme down. I've helped a friend do his 2005 F-150 CrewCab truck, the before and after was clear as day. He even decided against upgrading his stereo/speakers because he could hear the stock setup a whole lot better.

Glenn
05-08-2009, 06:24 AM
We are talking about a dual purpose DD/race car here with 680 HP that adding all that weight to is just not going to happen. You got to know the people on the net and their cars before making statements.

Glenn Ford :flamer:

magindat
05-08-2009, 06:29 AM
Brian,
First, don't kill yourself with brand-name dynamat. I'll give you my contact for the generic stuff. Works just as well.
The noise she's bothered with is probably actually the resonance from the headers. It happens to be at about 2500-3500 hz in normal driving. This is the same frequency at which a baby cries. Wonder why it bothers her?
A nice square of dynamat on the firewall where it starts to angle up will help block the resonance passing into the cabin.
To stop the resonance altogether, dump the headers into a baffle muffler. They are simply a straight through pipe with louvers punched on the inside and a larger pipe outside and about 1/4" of glass in between. (like a cherry bomb, but louvers, not punches) Mine were about 20 bucks each. NEW. These take that resonance or characterisitic header 'ring' and make it go out the tailpipe instead of vibrating your fillings. Further, they make great fakey cats!
To help the sound system, spray Cascade inside the doors. Just be carefull not to spray it on your regulator. Remove all the trunk lining and spray the entire trunk including the sides. Trunk gets 2 coats. Cascade is WAY easier and I think better and CHEAPER than dynamat. The stuff comes out looking like rhino lining. DON'T use Cascade inthe interior, though. It rebounds and you may get some on your carpet or seats. You'll need about 5-6 cans total.
Guess these guys haven't met your 'better half'. Tell her I said :wave:!
Gimme a holler if you need more info.
All the best.
Rich

magindat
05-08-2009, 06:32 AM
We are talking about a dual purpose DD/race car here with 680 HP that adding all that weight to is just not going to happen. You got to know the people on the net and their cars before making statements.

Glenn Ford :flamer:

Cascade will provide the benefit without the weight.

mrjones
05-08-2009, 06:58 AM
How much does Dynamat weigh?

fastblackmerc
05-08-2009, 07:31 AM
I did the whole floor, the doors, the trunk divide, the rear shelf, the trunk shelf.
It worked great. Car is really quiet inside.
But did not use "Dynamat" .
http://www.motorcitymarauders.com/forums/showthread.php?t=6378&highlight=fatmat

+1 on the Fatmat! Will be doing the entire interior this summer. Did the trunk last year.

O's Fan Rich
05-08-2009, 07:42 AM
Cascade will provide the benefit without the weight.


Cascade?...... dishwasher detergent?....

What is this stuff, Rich?

babbage
05-08-2009, 11:33 AM
Replace your X pipe with one like this (Magnaflow Tru-X) - it's still straight through but it's QUIET. Dynamat Extreme on the Firewall and UNDER the car between pipes and car body will help. This is a picture of MY old car. I did this too keep the exhaust quiet, never tried a traditional X Pipe.



http://www.nationalgunday.com/magnaflow/exhaust1.jpg

magindat
05-08-2009, 01:46 PM
Cascade?...... dishwasher detergent?....

What is this stuff, Rich?

http://www.cascadeaudio.com/car_noise_control/vb_1s.htm

http://www.cascadeaudio.com/car_noise_control/art/VB1S-PRO-Bumper-Cover.gif

magindat
05-08-2009, 01:49 PM
Same results - far less work. No bending, twisting or squeezing into small spaces for this fat guy!

O's Fan Rich
05-08-2009, 01:57 PM
Same results - far less work. No bending, twisting or squeezing into small spaces for this fat guy!

Easy Squeezy Lemon Peezy!

Thanks, Rich!

Joe Walsh
05-08-2009, 02:06 PM
How much does Dynamat weigh?

A LOT!

We DynaMat'ed the floor boards and the inside rear wheel wells of the Cobra for a quieter ride.*

The roll of DynaMat weighed a ton!
It felt like an 80# bag of cement.

*I know....I know...it was kind of dumb, seeing as you have a pair of 4" side pipes less than 3 feet from your ears.
But it is a VERY quiet car when you have the ignition 'OFF'....:P

FordNut
05-08-2009, 07:53 PM
Alright, today was spent in the garage laying Dynamat. I bought it last year when Eastwood had a sale on it, been carrying it around in the trunk forever. Actually the box was in the trunk when I ran the 11.64 at SSHS last November.

The main focus of the thread was to figure out where to start. I pulled the rear seat and package tray out. Started at the edge of the package tray, about 2" over the edge. Layed it over the fenderwells, behind the seat, under the seat all the way to the floor pans. We'll see how that works first, then go from there.

Didn't want to cover the whole package tray, since I've got the basslink in the trunk I'd like to hear it at least a little bit.

Rich, thanks for the info on the Cascade spray-on insulation. If I do the doors and inside the trunk I'll for sure use that instead of Dynamat. My hands are cut all to pieces, that Dynamat stuff is SHARP.

Is the Fatmat lighter than Dynamat? If I pull the carpet and do the floors I might try something different.

I still have a couple of sheets of Dynamat, I might try the idea of putting it on underneath the car, between the mufflers and floor pan.

Another spot that has been suggested for treatment is the front floor pans in the area of the headers. I may try that one soon too.

O's Fan Rich
05-09-2009, 05:17 AM
Brian, FatMat has at least two sizes (thickness) on Ebay... I used the thinner stuff.

FordNut
05-09-2009, 06:33 AM
To stop the resonance altogether, dump the headers into a baffle muffler. They are simply a straight through pipe with louvers punched on the inside and a larger pipe outside and about 1/4" of glass in between. (like a cherry bomb, but louvers, not punches) Mine were about 20 bucks each. NEW. These take that resonance or characterisitic header 'ring' and make it go out the tailpipe instead of vibrating your fillings. Further, they make great fakey cats!


I was thinking about putting somethin like this in the pipes alongside the driveshaft, between the x-pipe and the mufflers. I'd like to find some made with stainless, though.

cougar9150
05-09-2009, 11:43 AM
I wouldn't recommend Dyna mat for exterior. It will probably peal off unless you get the under hood liner version or something designed to block sound and heat if it's going to be near headers or exhaust. I would look at something similar to this: http://www.designengineering.com/products.asp?m=sp&pid=27
You need something that will reflect the heat away, dampen sound, and still stay attached near a heat source when exposed to the environment.
The Cascade works good also. I did it in my trunk the 2 weeks before crash. It never quite dried on the foam(?) sealant in the trunk corners. I wiped the sealant clean with some IPA. Overall it really improved my interior sound, greatly reducing road noise. On the can it says it can be spayed as an under coating also. It's easy to apply just cover what you don't want over spray on, and make sure there is no wind. Same rules apply as when applying spray paint.

magindat
05-09-2009, 04:55 PM
I wouldn't recommend Dyna mat for exterior.
It WILL peel with heat and moisture. And probly stick to the drive shaft.

FordNut
05-09-2009, 10:28 PM
OK, I won't try that then.

Once again this project snowballed. While the sail panels were out, I figured I might as well install the tweeters I've been carrying around in the trunk for about 3-4 years. Then I figured I might as well install the crossovers too. And wires. And wires for the woofers (didn't install them yet, just ran the wires). To do all that I had to empty the trunk. Then re-organize the trunk so (almost) all the junk I'm still carrying around will fit in the organizer. I'll have a little more space in there when the woofers are installed.

If I had been smart about it, I would have done the Cascade treatment while the trunk was empty. Oh, well there's always another day.