Soundproofing???

[EvilEyez]

I have a bassani o/r x pipe and bassani catback on my 2003 cobra. I love the sound, but it gets pretty loud at hiwy speeds. Just wondering if anyone has a similar set and if you've used any soundproofing and if it's helped?

2003 cobra
dyno 396rwhp before mods.

 

[drizztkun]

I would assume some dynomat(sp) would help

 

[ProKiller]

heat shield around the transmission tunnel helped me out after the T3550 install. tranny was loud, helped out alot. i would assume putting it along the floor would help, but so would dynomat.

 

[Red2000GT]

Put the sound deadener on the floor right behind the seats as that's where the mufflers are. The thicker the better.

 

[therunyan]

Had similar issues (after market cat back, bushing swap and end-to-end cold air kit with no silencer). Got very VERY loud. I covered the entire passenger compartment (under carpet from as high up on the fire wall as I could go to back through the rear seats) with layer of dynamat extreme and a layer of l-comp (off-brand, thicker padding with lead buffer layer) over the top of that; in the doors and and trunk section I used dynamat extreme. It's a ton of money and work to do right (I probably have about $400 - $500 in material and 20 hours labor), but road sound is back to about where it was from the factory and the stereo sounds 100% better. I'd do it again.

 

[EvilEyez]

Had similar issues (after market cat back, bushing swap and end-to-end cold air kit with no silencer). Got very VERY loud. I covered the entire passenger compartment (under carpet from as high up on the fire wall as I could go to back through the rear seats) with layer of dynamat extreme and a layer of l-comp (off-brand, thicker padding with lead buffer layer) over the top of that; in the doors and and trunk section I used dynamat extreme. It's a ton of money and work to do right (I probably have about $400 - $500 in material and 20 hours labor), but road sound is back to about where it was from the factory and the stereo sounds 100% better. I'd do it again.

Thanks for the info. I was hoping someone had the same problem with a solution. I've been reading up on Fatmat and Secondskin soundproofing. I'll pick one and go at it. Maybe I'll be able to hear my tunes afterwards. Thanks again.

 

[therunyan]

Thanks for the info. I was hoping someone had the same problem with a solution. I've been reading up on Fatmat and Secondskin soundproofing. I'll pick one and go at it. Maybe I'll be able to hear my tunes afterwards. Thanks again.

No problem -- A bit of unsolicited but sound (IMHO) advice: Go at it slowly, and follow the instructions. The stuff is great if applied right, a waste of time and money if done wrong. The dyanamat/Fatmat/brownbread stuff (sticky, with foil back), absolutely must make contact/stick to the metal surface to dampen properly. Using smaller pieces, it was easy to make good contact -- larger ones will tend to stick on themselves, get wrinkles, etc.

Since your sound issues are maily due to the cat-back, start in the trunk (pull all the panels, carpet and yank out the spare tire) and cover all the metal you see, put it back together and driver her around the block. That will give you a decent idea of whether it's worth it to move forward (mine was night/day).

Best of luck with the project!!

 

[Tylerb59]

No problem -- A bit of unsolicited but sound (IMHO) advice: Go at it slowly, and follow the instructions. The stuff is great if applied right, a waste of time and money if done wrong. The dyanamat/Fatmat/brownbread stuff (sticky, with foil back), absolutely must make contact/stick to the metal surface to dampen properly. Using smaller pieces, it was easy to make good contact -- larger ones will tend to stick on themselves, get wrinkles, etc.

Since your sound issues are maily due to the cat-back, start in the trunk (pull all the panels, carpet and yank out the spare tire) and cover all the metal you see, put it back together and driver her around the block. That will give you a decent idea of whether it's worth it to move forward (mine was night/day).

Best of luck with the project!!

Old post, sorry for bringing this up...

How much of that dynamat will I need to cover the entire floor in a 99+ from the firewall back through to the trunk (and perhaps a little bit for the doors also)?

( http://www.ikesound.com/product-product_id/546 )

This will make for a nice winter project.

Thanks,

 

[myponyrocks]

lets put it this way, the "trunk kit" from dynomat covers only 70% of the trunk not including the trunk lid, and thats almost or more than 100 skins depending on where you buy.

I only did my trunk for audi, but what I did was buy a gallon of liquid SD from ebay, then put the dynomat in the big problem areas of the trunk (brake light housings, fuel intake ((Where you gas up)), and the wheel wells. Sound difference? You bet! Would it be better with only dynomat? I'm sure, but I feel better knwoing that I only paid 150 to do the entire trunk

 

[MyEarsHurt]

I used over 40 sq ft on my stang, did the floor, under the rear seat, whole trunk including lid, and doors. It wasnt that expensive cause I got bulk packs for cheap from a friend that worked at Best Buy. Anyway, dynamat extreme is helpful, and so is carpet padding. I used that in my trunk to fill some spaces, that helped a little, but that helped more with rattling than soundproofing. Oh BTW, I can still hear my exhaust pretty clear at high speeds, its the price to pay for not having cats...

 

[Tylerb59]

Ah, thanks for the heads up.

So I take it I'm going to need two of these? I imagine I'll have a little bit left over, but that might allow me to put some on the doors and double up on other areas, eh?

http://www.ikesound.com/product-product_id/546

 

[therunyan]

Ah, thanks for the heads up.

So I take it I'm going to need two of these? I imagine I'll have a little bit left over, but that might allow me to put some on the doors and double up on other areas, eh?

http://www.ikesound.com/product-product_id/546

Yeah, if I recall correctly, two bulk packs like that should be more than adequate for the trunk space. (and the carpet pad idea, above, is another good, very inexpensive top layer: The way I understand Dynamat is that it really deadens noises carried by vibrations in the metal, which is why it won't work very well if it doesn't make really good contact with the metal surfaces. While my understanding may be wrong, I believe that the thicker products (L-Comp for example - http://www.b-quiet.com/lcomp.html) take care of deadening the deeper "bass" sounds becasue of the thicker, spongy foam and lead barrier). So a layer of carpet padding (in lieu of the much more expensive L-Comp type products) over the top of the dynamat should help dampen some of the deeper decible sounds (of course, not as much as the proprietary products). I put L-Comp in the passenger compartment in areas where the dynamat wasn't going to stick (such as the floor boards and up the fire wall) which really makes the interior very quiet (I can hardly hear my exhaust now). Note: if you have any of the dynamat left over after coating the trunk, use it in the doors -- not only does it dramatically reduce cabin noise, but they close with that quality, firm Mercedes-like "thump."

 

[98stangv8]

I used about 2.5 packs of the 36 sq feet of extreme dynamat...and it works great! I got it for 90 bucks per 36 sq ft pack. i still have about 23 sq feet left...I covered the entire cab, doors, trunklid and entire trunk:

 

[myponyrocks]

that trunk kit only comes with 5 sheets I think (might have been 6) any way with two kits you should be able to cover the entire thing AND use the excess on the problem areas I mentioned above, double coverage does wonders. That kits a way better deal coming with 9 sheets, I would think 9 sheets would cover everything except the trunk lid (It might cover it, but it wouldnt be pretty cause Itd probly be scraps.