I have noticed on two 1990 IROC-Z cars I own, that the heater/A/C box has been damaged from header heat. The first one was actually melted to the point that you could see the evaporator core. The second one melted the foam insulation inside the box.

The damage was done prior to me owning the cars.

I bought a 12"X12" piece of heat barrier ( Cool It Thermo Tec Summit #THE-13500) which is adhesive backed, and I had planned to install it onto the outside of the box between it and the headers. Upon receiving it, the instructions state that it can be good up to 2000 degrees. But the adhesive backing is only good for 300 degrees! Not wanting to take a chance with this stuff, I am also planning on using some of the Thermo Tec Clamp-On Heat Shields (Summit part# THE-11630). I want to keep my A/C.

Does anyone have any experience with this product, or this problem?

 

Mine crumbled taking it out to put a regular heater setup in. Use that thermal deal on the box, it'll stand up to the heat just fine.

 

Are you running extremely lean?

 

I don't think it/they were running lean. I see you are from Pensacola, that is where the car came from! You may have seen it running around down there a couple of years ago, a white 1990 IROC-Z with two black stripes front to back over the hood and hatch.

 

There are a lot of thirdgen Camaros running around this town, so forgive if I say I can't recall that one car in particular. Sounds like a cool car, though.

I only asked about running lean because I know that headers can get EXTREMELY hot in a lean condition (1,300 degrees F and higher). That would definately be enough to melt plastic, even if it wasn't relatively "that close" to the box.