AddictedA4

Anyone have recommendation for design?
thanks for time

squidix9

There are lost of different materials and techniques. It depends on what and where though.

Under my manifold I have a sheet of plain gasket material, it helps keep the heat from rising up under the manifold.

Around the intake, I have some thin metal faced insulation.

For inside you can find foil faced insulating sheets.

At most speed shops you can find header wrap in strips for reducing heat too. Just watch out most header manufacturers recommend not using it.

cuatrokoop

keeping the heat in like that (not insulating the inside and outside) will fatigue the metal much faster due to the retained heat. Getting a cast EM extrude-honed and then JetHot coated would be a good idea. Getting a JetHot coating on a tubular header would also work well and not significantly reduce the header ID.

squidix9

just the parts that are near the exhaust manifold, and the intake from the rest of the heat producing parts.

My engine run very hot, on a hot day you don't want to lay your hand on the hood.

cuatrokoop

I think all 20v's get pretty darn hot. I know that my car would actually run hot enough to cause any voids in my glass hood to bubble up on the top surface. After seeing that, I pulled the glass hood off and am working on redoing the top 1/16th of an inch or so of the glass. It turned out to have a LOT of voids in it

I doubt my car runs as hot as yours, but I do know what you are saying!

Ideally, the IM and header would be JetHot'd (or similar) due to the "wonderful" IM design Audi had to use in the B3 20v's. The airbox has plenty of shielding on it, both yours and the factory version. Yours is more built in though, as its kevlar or whatever ;-)

squidix9

airbox has no shielding at all. It's relying on the stock aluminum exhaust shield from the factory. But by luck or whatever, it doesn't seem to get ho like the rest of the compartment. I've got another hood coming, so I may decide to experiment with some hood vents.

cuatrokoop

I am thinking about sticking a vent over the turbo area in my glass hood (its down to the bare glass right now, so it wouldn't be a big deal to add a vent in). Not sure it'd really help me all that much though, at least not while under-way.

And like I said, I think the fact that you have a composite airbox greatly helps out its heat-rejection. Saves weight in more than one way (lighter than the plastic, and no addition heat shield, two birds, one stone).