??????That kinda defeats the purpose of the dynamat doesn’t it?
Tunnel insulation effectivenesss
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
Tunnel insulation effectivenesss
I plan on using a heat and sound barrier such as Dynamat under my carpet. My question is should I also replace the insulation that was under the car in the transmission tunnel? Or is this not effective and more for correctness than anything else.
I guess my real question is whats the best way to keep as much heat out of the passenger area?
I guess my real question is whats the best way to keep as much heat out of the passenger area?
Pro
Joined: Feb 2006
Posts: 649
Likes: 10
From: Shelby Twp MI
I'm doing this now, a layer of Dynamat Extreme is down and I plan to put a layer of Reflectix (from Home Depot/Lowes) up front to try and block some of the engine heat coming in. As for the carpet pad, I'll probably have that too locally where you would step.
By the way, you will need 2 packs of the 36 sq foot dynamat if you plan to do the entire interior! Cheapest price is on Ebay.
By the way, you will need 2 packs of the 36 sq foot dynamat if you plan to do the entire interior! Cheapest price is on Ebay.
Racer
Joined: Apr 2008
Posts: 418
Likes: 0
From: destin fl
Racer
Joined: Apr 2008
Posts: 418
Likes: 0
From: destin fl
I don't know. I have never had sound heat up an interior of a car as far as I know. If dynamat will not deter heat, why not use both products? I am assuming that reflectix will help the heat issue, and the dynamat will help the noise issue. I am about to put the interior back in my vette, and want to do the right thing.
Burning Brakes
Joined: Aug 2007
Posts: 1,173
Likes: 1
From: Liberty Missouri
I don't know. I have never had sound heat up an interior of a car as far as I know. If dynamat will not deter heat, why not use both products? I am assuming that reflectix will help the heat issue, and the dynamat will help the noise issue. I am about to put the interior back in my vette, and want to do the right thing.
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Racer
Joined: Apr 2008
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From: destin fl
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
An auto tranny has a separate heat shield that fits over the tranny main case and a foam "seal" the fits between the leading edge of that heat shield and the bottom of the floor pan. They are needed to effectively reduce tranny heat. Reflectix alone won't do that job; but Reflectix over the entire tunnel, in addition to those items, would be of significant benefit. Also, put it under the radio an up the inside of the firewall as far as you can conveniently reach.
Thread Starter
Drifting
Joined: Jun 2006
Posts: 1,912
Likes: 12
From: Schaumburg (Chicago) Illinois
I appreciate the info so far but I still need some clarification. In the tranny tunnel the car originally had some sort of insulation that attached to the body not the transmission. Is this what you are reffering to?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
I think the only insulation on top of the tranny tunnel was some pieces of that thick jute padding. That stuff isn't very effective. I'd pitch it, if you're going to install Reflectix over the entire tunnel area.
Racer
Joined: May 2005
Posts: 417
Likes: 0
From: Red Deer Alberta
I think that collar you are referring to sits on the top front of the transmission and redirects the hot air from the engine bay down and away from the cockpit floor. I bought one and will be installing it. They're not expensive and were a good idea in 1969 ??
Melting Slicks
Joined: Apr 1999
Posts: 2,675
Likes: 13
From: Sudbury MA
Put the original heat shield inside the transmission tunnel under the body and attache it to the clips that are there.
This provides additional insulation between the trnasmission and the body and will make it that much easier for your Dynomat and Reflectix to do its job.
You will likely have to drop your tranny to get the preformed aluminum & fiberglass tunnel insulation properly fitted and onto the retaining clips that are mounted under the body inside the transmission tunnel. Careful, they can be sharp.
That's what I had to do on my 68
Kurt
This provides additional insulation between the trnasmission and the body and will make it that much easier for your Dynomat and Reflectix to do its job.
You will likely have to drop your tranny to get the preformed aluminum & fiberglass tunnel insulation properly fitted and onto the retaining clips that are mounted under the body inside the transmission tunnel. Careful, they can be sharp.
That's what I had to do on my 68
Kurt
Racer
Joined: Feb 2008
Posts: 497
Likes: 0
From: Streator Illinois
I just finished today repairing seats and installing Reflectix only. With 3" true duals with Magnaflows in a convertible, sound coming through the floor isn't an issue.
Terry
Burning Brakes
Joined: Aug 2007
Posts: 1,173
Likes: 1
From: Liberty Missouri
I am going to disagree with others and say yes. It would seem to me that putting down Dynamat under the heat barrier would allow heat through the Dynamat to the point that when it reaches the Reflectix, heat would be radiated back through the sound barrier and would cause it to rise in temp. Makes no sense not to put down heat barrier first to keep the heat farther away from the carpet. Can't see any reason why the sound barrier wouldn't work in either location
I just finished today repairing seats and installing Reflectix only. With 3" true duals with Magnaflows in a convertible, sound coming through the floor isn't an issue.
Terry
I just finished today repairing seats and installing Reflectix only. With 3" true duals with Magnaflows in a convertible, sound coming through the floor isn't an issue.
Terry
The dynamat works by stopping or deadening the sound vibrations that run through the body of the car. If you put down insulation first the vibrations will still travel freely under the dynamat. The dynamat isn’t a heat insulator so it doesn’t reflect heat back up enough to cause a problem. I used dynamat then insulation over the top in my car it’s cool and quiet. It was a huge improvement over stock.