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69 Mustang with a 408 stroker in it. The headers we installed sit higher up than many of the other options because they had to clear the suspension. And I think when its really hot outside (90F+) that they're putting off so much heat that its cooking the carb and causing poor performance and misfires. I'd hate to have to wrap them or pull them out and get them coated. Are there other options to try first that would increase airflow and help pull that hot air down and away from the engine bay?
 

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Wraps do cool things off, but also tend to cause headers to corrode away to nothing in a few years. Ceramic coating is the best choice for headers you want to keep, as well as cooler underhood temps.

It's also a great idea to use a phenolic spacer so your intake can't transfer so much heat upward into the carb and bowls.
 

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I've been dealing with similar issues on mine, and I've thought of several fixes and tried others. For instance, a plastic spacer and aluminum heat shield didn't do much.
For ideas I haven't tried:
-Duct outside air to blow on the carburetor itself.
-If you have a Holley 4150 style carb, put another set of inlet lines on the other side of the fuel bowls with a restrictor (such as a pressure regulator) to act as a return line, allowing fresh fuel to cool the carb.
-Insulate the fuel line to the carb.
-Block off the exhaust crossover in the intake or run an air gap intake.
-If you have A/C, run the fuel line along the line from the condenser to the cabin to cool the fuel.
-Vent the hood to allow excess heat out.
 
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That A/C line idea is really clever, Paul! If a fellow was to make some kind of aluminum block with fittings for both fuel and A/C so it could effectively transfer heat, and then insulate the outside of it to keep it from soaking underhood temps, I wonder how much of an actual effect that would have? Even a 10-20 degree difference in intake temp can have a pretty significant impact on power, so it might be genuinely worth doing.

Anyway, great ideas, and nice post.
 

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It might actually be best to use the line from the cabin to the compressor, since that's after the evaporator, where it gets cold. But yeah, whichever one is cold, do that.
 
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What we use to do to address this is to take a piece of aluminum (or gal. sheet metal will work as well but not as effective) and cut it to place inbetween the carb and intake with it extended 3-4 inches away from the outside of the carb...this keeps the fuel lines and carb bowl shielded from heat
 
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