Yeah I had already thought of that Ideally you would want to replace the gasket between the engine and the intake manifold.

 

http://cgi.ebay.com/ebaymotors/ws/eB...tchlink:top:us

 

I saw them on a speed world challenge integra several years ago. I wish I had taken a picture. It was about 1/2" thick. some sort of a white plastic.

 

I do not believe for one minute that a plastic will with stand 500*, much less 800*. Maybe some thermosets can repeatably go to 500* for a short time but they will eventually die.

The stuff I've used in industrial applications was hard, had fiberglass in it, was 1/4" thick, comes in many colors, and rated at 500*. Reminded me of highly compressed drywall stuff (if that makes sense) with visable fiberglass stranding. Machinable and turned to dust when doing so. You should pretect yourself from the dust.

We use the hand held infra-red thermometers to monitor stuff. I can vouch for the fact that it reduces thermal transfer. But as one poster already pointed out, There is heat soak in an engine compartment other than that from contact.

 

as far as temperature i do not know, but changing the length of intake runners changes the power band. Putting in a large spacer would change intake velocity, and make more difference in that aspect rather than temperatures.

A good example of this can be found in the variable intake tubes on the 787B...