Originally posted by armstrkw:
The darkness has nothing to do with it bro. If the heat shield is black it will basically hold on to any heat radiated against it; Causing it to heat up a bit, and thus the intake temp to be slightly higher. If however the shield is white, whatever heat gets radiated to the shield has a better chance of being reflected to the engine bay and not the inside of the intake itself. If you want, do a search for ??back body? or something to that effect. White may not look as nice but, it is the best solution. Insolating the hell out of it should let you pick any color you would like.
-2 cents
You are right about the issue of a lighter color compared to a darker color for heat radiation. But I think the effect of the color is minimal compared to the material the heat shield is made of. The thermal conductivity of the material is a more important issue. A metal will conduct more heat than plastic. Conduction: Aluminum > Stainless steel > plastic (e.g. polyethylene).
Reducing heat radiation and conductivity through the heat shield still don't seem as important as just blocking the hot air. If your engine sucks cold air past a hot heat shield (depending on the rate of air flow) I don't think it will have enough time to get hot before entering your engine. So in my opinion, I think the issue is just blocking hot air.
Just my 2 cents.
06 Mustang GT - stock
96 SE V6 5spd Midnight Red - 15.9 @ 86.8
150K miles
Mods: Bilstein struts, H&R springs, Borla Cat-Back, Brullen y-pipe, Gutted Precats, SVT UIM+LIM+TB, K&N FIPK, , DMD, Magnecor KV85
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