Heat reduction in the cab

#1
While I have my trans and tcase removed to swap in my rebuilt t18 I want to apply some kind of coating on the underside of the transmission tunnel and floors to reduce the amount of heat (and hopefully noise) that make it into the cab. Do any of you have experience with any products for this purpose? It needs to either be a waterproof coating or be able to apply on top of a water proof coating or to have a WP coating applied on top of it.

Some possibilities:
1.Pep Boys has a rubberized coating I used in my wheel wells to make them easier to clean. It reduced the amount of noise, but I doubt it did much for heat. I might could use this for a base layer (to reduce noise) and apply a radiant heat barrier coating (shiny!) on top to reflect radiant heat, but it wouldn't do anything for convection/conduction. I need to check about the compatibility/price of the two products.
2. Use a rubberized product to coat everything. Then put a heat shield to block radiant heat from just the exhaust. Obviously this leaves a lot of area for heat to still get to the cab.
3. Use an undercoating product of some sort that claims to reduce heat and noise - these tend to be expensive, and some require spray application.

I wanna stay away from any products that go on the interior. I have bedlined the interior of the tub and want to keep it that way.

What other methods or specific products should I pay attention to?

Thanks!
-Gareth
 
#3
There are several ways to go about this, but the easy way is to get some self adhesive sheilding. There's a glass matt with self adhesive on the back, and a metallic tinfoil kinda coating on the face. Stuff works great, I'll see if I can still get it cheap.
 
#5
ditto Brook's question. That may be the easiest way, but it also seems to be the easiest way to encourage your floorboards to rust out. I need something that keeps water away from metal.
 
#7
The cloth I don't like: I want to use something that seals and prevents moisture from being trapped against metal, and it says you rivet it in place - no thanks! The LizardSkin looks great except for 2 things: 1) I don't want to have to use spray equipment if I don't have to 2) It appears to only be available in 2 gallon containers. I think I'll need 1 to 2 quarts.

Here are a couple things I found in the Eastwood catalog but haven't done any research on them yet:
http://www.eastwood.com/eastwood-s-rubberized-undercoating.html
http://www.eastwood.com/eastwood-s-flexible-sealer-and-sound-deadener.html

And this is a product that is designed for use as a radiant barrier in homes, but it seems it would work fine for automotive applications.
http://www.solec.org/LOMITMenu.htm

I'm wondering if a combination of sound-deadening rubberized undercoating covered with the radiant barrier paint might give me the combo I desire in a much less expensive package than Lizard skin or a product like it.

FYI- The shiny radiant barrier would have to be applied on top of the undercoating because it is the reflective properties of the barrier that make it effective. This is true in homes, too. There has to be air space next to the radiant barrier for it to be effective.
 
#8
Meh on all that stuff. I mean, it helps but it won't help you THAT much.

Really if you want to shield yourself, get some heat shielding, its what is used on all newer cars with great success. I just added heat shielding on my rover exhaust and HOLY CRAP it is amazing. Seriously, its great. I'd look around in some junk yards, all new cars have transmission heat shields (or at least the ones I've crawled under).

To add to that, a couple of the restorers around here are using spray in insulation (as in, paint-like). I know xtreme 4x4 did something like that on their project JK, so go forage around on their website. For about the same price, you can have great insulation both heat and noise without any of the bulk. I checked it out a couple months ago for my rover, they sell heat and sound spray-in insulation and its like paint. Same thickness. Sure, you are gonna pay a little bit more but I think its going to be worth it.

Also no cutting or fitting, just spray the SOB in there. Layer up if you are concerned. Will be the same thickness as paint. Recently talked to Lotus Europa, Porsche 914 and a BMW E30 owners with the spray in paint-like insulation. All love them, especially the BMW guy. Apparently the factory insulation weighs A LOT so he shed the weight and had better insulation. Hard to beat that. Same for the Europa and 914 driver. Made the car so much more comfortable but not adding any weight (both are lightweight cars).

I've put all kind of insulation on my rover (basically a non-insulated in any way vehicle) and yeah, it helps but none of it other than the heat shielding has been the end-all amazingness. I can tell a difference but not enough for me to recommend. In the future when I do my teardown, I'll do the paint-insulation stuff.
 
#9
My 03 came with a heat shield that bolts to the trans tunnel underneath. It hangs down 1/2" to guard against moisture. The front carpet also has a shield on the underside.
 
#10
Max, are you talking about putting a piece of metal between the exhaust and the vehicle or are you talking about an engineered part that is specially designed? Heck, will you do me a favor and just take a pic of what you did for your rover? I'm also interested to see how much of the exhaust you're shielding to have the effect that you're so excited about.

The Lo/Mit product I posted a link to is a heat shield that is painted on. Basically it reduces the emissivity of the panel it is applied to. I need to do some checks on it, but I'm wondering if its a product that could be applied to the floorpans the reduce heat gain from radiant heat and apply it also to the exhaust to reduce the amount of heat that is emitted. What I was describing before about applying the Lo/Mit on top of a sound deadening undercoating was an idea I'm throwing around to basically create a combo that is as effective as the LizardSkin or other products that are used for sound deadening and heat reducing insulation.

I'll look under my car and truck after the ground dries up some to see what kind of heat shielding is there.

Thanks for the input guys!
 
#11
It all depends on where the heat is coming from. The lizard skin ceramic paint is supposed to be pretty good, but I have never tried it. Getting the majority of the heat out of the engine bay is probably the best way. I ran the cloth header wrap on my exhaust and it made a world of difference in the cab of the buggy. After a couple hours of wheeling without it, the tubes in the center were so hot you could burn your leg and the floors would fry an egg or melt your boots. (right dean?). With the wrap I can wheel all day and the interior still gets a little warm, but not anywhere close to the same as it was.

A big problem for our rigs is that we skid plate the entire underside. This forces the hot air to start at the radiator and work its way all the way out the back. Inevitably this puts more heat into the metal. I was worried about the cloth with mud and stuff but for the money it is the right solution. Ceramic coating would be better but costs 10x as much. Another way is to get the hot air out of the engine bay before it gets into the trans tunnel. I have seen lots of hood vents and fender vents that help get the hot air out before it gets to the cab. Heat shields on the exhaust help a ton too. Just use some 20 gauge sheetmetal and make what you need. It is easy to hand form and you can tack weld 1/4" bolts to the exhaust and bolt the shield down.
 
Top