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Old 11-20-2008, 02:03 AM   #33 (permalink)
Christ
Moderate your Moderation.
 
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Quote:
Originally Posted by trebuchet03 View Post

But - I'm not concerned of convection off a warm hood.... It the heated air in the engine bay - if it's not heating the hood, it's going to try and go elsewhere unless something stops it from physically moving out of seams, cracks etc.
Obviously... it's still going to expand and cool and it would be very difficult to physically contain all that heat... but thermal diffusion from the hood (IMO, anyway) is one of the major places that the heat goes when it's not properly insulated.

As was stated previously, adding a grille block and largely limiting dynamic flow through the engine bay may be a pre-requisite for a reflective blanky to actually do something, but most of us have that already anyway. Maybe it's that extra 1 or 2 mpg that keeps us able to drive when gas prices go back up?

Won't know until it's tested. I mentioned roofing felt and aluminum foil or mylar the other day simply because they're both alot cheaper than dynamat... stuff is wayyy too expensive for what it does. (poorly, at best)
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