I just received my order for my firewall insulation and I'm very pleased. I ordered it from eBay and it arrived quickly. I pulled it out of the box and unrolled it and it feels like it is very high quality. I think it will look great and it should perform great as well. The product is called MightyMatt and I got the 1/2 inch thickness with reflective foil on one side. I'm not associated with the company in any way. Here is a link to the eBay auction.
I'll be putting it into my '85 and I'll be sure to show pics in my build thread linked in my signature.
------------------ Jonathan 23K mile '85 notchie w/ 88 cradle, '87 2.8/Getrag, Air, PW, PDL, PM - Still under construction http://www.fiero.nl/forum/Forum2/HTML/121056.html I'm not a mechanic but I play one in my garage - me Power tends to corrupt, and absolute power corrupts absolutely - Lord Acton Those who hammer their guns into plows will plow for those who do not - Thomas Jefferson The tree of liberty must be refreshed from time to time, with the blood of patriots and tyrants - Thomas Jefferson
I was searching Ebay and found this product as well, and ordered some today. They now make it with foil on both sides, and you can get 1/4" or 1/2" thickness. I wanted something to give some heat protection as well as be resistant to underhood temps. This stuff is Heat resistant up to 1200 degrees. They have a great video showing how well it protects on You-Tube.
I would imagine that this could be painted- it's just aluminum foil, so standard paint prep ( maybe use sand free instead of sanding)
I found a different product that was black (Dynaliner made by Dynamat), but it doesn't have the same high heat capability. It is sold as an Underhood Insulator in black, or available in silver as Hoodliner-- good to 225F or so.
I haven't used it yet, but I baught some of this Lava Mat. It has a carbonfiber look and has good heat protection. I'm going to do my bumper exhaust pockets in it. If it goes good I'll do the whole firewall in it too. Not cheap stuff though! https://www.heatshieldproducts.com/lava-shield
[This message has been edited by Bridgetown (edited 01-30-2016).]
I see a LOT of firewalls on different cars, along with fenderwells, at car shows now painted with bedliner. As for just painting the aluminum, rubberized undercoating will work just fine, and can be painted over with even body color if you want. NO prep required other than cleaning off grease and oil.
Reporting back after installing my Lava sheild insulation. It's nice stuff to work with and installs easy. It looks nice once it's in. Similar to carbon fiber. It reminds me of the carbon tubs used on exotics. I haven't put the engine in to get impressions on sound/heat suppression yet. I'll report back once the engine is in.