Best material for heat shielding intake
 

There seems to be quite a bit of heat shielding products out. Most of which contain either a mirror like finish or textured aluminum outer coat. So I figured, I have this sheet aluminum laying around why not try it out? (apparently oxidized aluminum has as bad as 70% reflectivity of radiant heat vs up to 96% for polished surface, I've read)

http://i174.photobucket.com/albums/w...FFB2859ED3.jpg

This loosely attached (double sided foam tape) aluminum sheet doesn't seem to be doing much in terms of keeping heat off the intake. Although surface temps seems to be a good amount lower on the aluminum compared to the plastic airbox.

I'm guessing I will have to try out these specific products to get the job done right. But, I'm not sure what will work better. Most of these product advertise 95% reflectivity or more, but you know what they say about ads...

So what better for this purpose?

Gold foil tape?
http://i174.photobucket.com/albums/w...0B5315C09D.jpg

Silver foil tape?
http://b.cdnbrm.com/images/products/..._foil_tape.jpg

Aluminum coated fiber?
http://www.jegs.com/images/photos/500/555/555-32031.jpg

Or this kinda thing?
http://b.cdnbrm.com/images/products/...cky_shield.jpg

Or is there any way to make the sheet aluminum I do have work for my purpose?