[VAB5]

'69 LeMans Convertible, Pypes 2.5" exhaust w/ x-pipe, unequal length Dynomax Turbo mufflers, and the drone is awful.

Who makes the best sound deadening mat? Going to try that first before playing with mufflers.

Paul

[AZ64GP]

I've heard that the sound/heat insulating mat for wrapping around HVAC ductwork that you can find any home improvement store works very well. It's peel-and-stick just like the sound/heat mats you see for cars, works very well, and it's about 2/3rds the price of buying the actual sound mat for cars. I heard this from an old timer who has restored several old cars. That's probably what I am going to use when I get to the interior of my '64 Grand Prix.

I don't personally have any experience though with the various sound/heat mats on the market for car interiors. If you don't want to go the route of the mats used for HVAC ductwork, I'd use whatever sound/heat matting you can find which is the most dense/greatest thickness for the least cost (i.e. bang for the buck).

[rohrt]

I used Damplifier pro on my car.

I will tell you now that it will not help with exhast drone. I also have drone with the dynomax turbo mufflers installed. I was using a strait through muffler before them and it was much worse.

I have some VT mufflers that I need to install.

[Bluesugar]

Well if this don't beat all!!..I thought I had done enough research on past threads and posts to warrant me buying a set of Dynomax Turbo muffs(which I did but haven't installed yet)because most said that they didn't drone like the Flowmasters!..Now I'm reading about how they drone!!..Now I'm droning and my wife doesn't want to here that!!

[66Post]

I used the asphalt paper from out host, figured it was good enough for the factory, it's OK with me. Seems to do a good job with elcheapo Summit turbo mufflers, but they drone to begin with.

[geeteeohguy]

A friend just did his '67 GTO with the Frost King foil and adhesive backed stuff from Lowes. Under $40 to do the whole car. Worked out very well, but he's running stock exhaust. If yours drones, you'll need to change the exhaust/mufflers, though.

[rohrt]

Originally Posted by Bluesugar

Well if this don't beat all!!..I thought I had done enough research on past threads and posts to warrant me buying a set of Dynomax Turbo muffs(which I did but haven't installed yet)because most said that they didn't drone like the Flowmasters!..Now I'm reading about how they drone!!..Now I'm droning and my wife doesn't want to here that!!

The Dynomax Turbos don't drone like flowmasters. They are much better.

You should read the exhaust drone thread in the exhaust section. On my bird I'm limited to a 14" case and i'm more suseptible to drone being its a convertible like the OP.

[ScottD3]

I used FatMat you can get it on ebay.

[mbwicz1]

I installed a kit from Eastwood in my car, and it was good to work with. I was a little short from completing the car, and bought some hushmat. The hushmat aluminum is very thin, which makes it pliable, except that it tears instead of stretches. The aluminum on the eastwood material is pretty heavy, and I could pound it into corners and it would stretch and form. Both stick well, I have no reservations reccomending the Eastwood product, I got it on sale for $119 for the kit. I was about 2 square feet short from firewall to rear wheel houses (I did not do the doors).

Mike

[bsblguy]

I used fat at for my trans am, floor, doors, roof, behind back seat and back side of door panels. Pretty happy with it.

[ponchjoe]

Originally Posted by ScottD3

I used FatMat you can get it on ebay.

X2.
I am having a hard time believing you have drone from Dynomax Super Turbos, they are one of the quietest mufflers you can buy. Jim Hand has a great deal of info on mufflers as far as flow and db goes in his book.

[HWYSTR455]

I used Dynamat on the clone, and though it is more expensive, I will use it on the rest of my cars when it comes time, it worked that good. I also used the Dynaliner over the Dynamat for a heat barrier, and with the two, it's amazing the difference.

I would imagine the Dynamat competitors are fairly close in performance, as long as thickness is maintained. The foil offers some heat barrier, but it's questionable how much, even with the thicker ones. It's radiant heat that' a problem in the interior, not reflective heat.

Some competitors or alternative products (like home use stuff) I've heard can run, slide, fall off, etc, so not all are created equal. I did enough homework on it that it was info-overload, gave up, and got Dynamat. But those drawbacks are some of what I heard.

You can wrap a muffler to help with drone, but they usually rot faster that way. But it does work. I have the Dynomax on the clone, picked the largest I could fit, (think they're 28"), the pipes exit out the back, and it's near dead silent IMO. (in the compartment)

.

[David Jones]

Roll foil backed rubber from Lowes, in the roofing section.
Followed that with Frost King closed cell, foil backed foam.
Made a huge difference in both heat and noise. Stays put too. Been there years. Removing it from my trans tunnel when I was installing my TKO was one of the more time consuming jobs in that project.
If your Dynomax Super Turbo's drone, you need to fix that. Mine....with 2.5" mandrel bent pipes are too quiet....and waaaay better than the 50 Series Flowmasters I took off.

[68 Firebird]

I used Dyna Mat and am impressed with product. easy to install and work with and
good sound and heat barrier.

amazon had the best deal for kit with free shipping.

Gerry C

[archerytony]

Originally Posted by ScottD3

I used FatMat you can get it on ebay.

I also used fat mat works great and I run 40 series flowmasters $120 did it.

[rohrt]

I spent a full day researching them all. They really only very by degree's in product quality. Price my be a different story. I went with the damplifier pro because of the good reviews, the thickness of the foil and mainly the fact that the foil is black and not silver. Personal preference.

[VAB5]

Originally Posted by ponchjoe

X2.
I am having a hard time believing you have drone from Dynomax Super Turbos, they are one of the quietest mufflers you can buy. Jim Hand has a great deal of info on mufflers as far as flow and db goes in his book.

I know! I started with Street Pros. Way too loud and droney. Switched to 14" Dynomax Super Turbos on both sides. Quieter, but still have drone. Got an 18" for one side, to have unequal length. No change. It's driving me nuts!

I'm going to try a mat first, which some have said will make it tolerable. Either way, it can't hurt. If that doesn't work, I'm taking it to an exhaust guy--we have a really good one not too far away.

[VAB5]

Anyone know the square footage for the entire passenger bay floor for a convertible (not doors).

[PMDRACER]

What did you guys do about the carpet install after putting in the sound deadening? Did you remove the padding from the back of the carpet to make up for the extra height of the mat?

[rohrt]

Originally Posted by PMDRACER

What did you guys do about the carpet install after putting in the sound deadening? Did you remove the padding from the back of the carpet to make up for the extra height of the mat?

I didn't the matting is only about 1/8'' In fact my only reget is not putting down an extra thermal blanket. I still have heat that comes through.