insulating firewall adhesive

[bighig340]

First let me say this is for a buddy working on a 1981 corvette. He said his interior is hot because of the engine giving off heat. He tried 3m and sticking the foil ontop of the flooring and the 3m got gooey when the heat built up. He is thinking of putting the insulation down ( it goes foil,padding,foil ) with the carpet on top but needs a heat proof adhesive. Any comments? Thanks alot.

[ShelbyDogg]

GE Pure silicone from the hardware store is good. It was invented by NASA.   It doesn't work on the heat-proof tiles but it'll work for that car floor.
Rob

[Stacked440]

If he wants to do it the so called "right" way which is usually the hard and expensive way, but look at Dynamat, they use it on overhaulin and such for sound and heat insulation.  Also he might want to try wrapping his headers in some heat wrap, thats the only thing i can think that would get really hot near the floors.

[crcarch]

I'm an architect and I saw this presentation for a new building product called Reflectix http://www.reflectixinc.com/.  It is a two-sided foil product that has an R-6 insulation value (Equal to more than 1" of rigid insulation) and it comes in a roll.  I see no reason it can't be used in a car.  As a matter of fact, it looks like Rev & Redline used it on their ride http://www.ridesthatrock.com/html/flooring.html and I've seen something similar listed in Year One but very expensive.  However, this stuff's cheap.  I bought a 16"w x 25 foot roll for less than $20 at Home Depot.  You can use the 3M spray adhesive to glue it to the floor and metal duct tape to seal it.  I'm going to use Dynamat directly on the metal, then Reflectix over that.  Should keep things cool and quiet.

[falcon50flier]

Posting mentioned adhesive, but many replies call out a blanket, so here goes any way.

If you want to control firewall and floor heat, see http://www.insulshield.net/pages/products.html - firewall blanket product. There is also Lizard Skin heat control.

GE industrial silicone adhesives (they are many formulations) are good to at least 300F. See Grainger (www.grainger.com) for a good selection and data sheets. There are also true intumescent adhesives, if fire retardant, as opposed to heat resistant, is the goal. 3M makes em and check Grainger for them too.

Also note standard Dynamat doesn't do anything for firewall heat, except get hot itself. A reflective on the interior side will help the interior temp, but will cook the Dynamat. Also note - Dynamat is 2 -3 times the price of generic PVC limp mass barrier sheet. They took advantage of the car audio market and built a strong brand, but the product is way overpriced. Insulshield above has a substantially lower price on the same stuff, and others can be found cheaper still if you're willing to forego the self-stick layer.

[Chryco Psycho]

there is aslo a ceramic brush on faom like heat & sound insulation product