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Can someone tell me, do cowl hoods usually offer any advantage such as better air flow under the hood (for cooling)? Do they usually fit over any the various upgraded blowers?

I currently have a cowl hood (not sure about the rise, maybe 2"?), but I'd like to go back to stock.
If anyone has a red one sitting around, and you're within reasonable driving distance of Durham, NC, give me a shout!
 
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10 second street truck
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I have never seen any empirical hard data to prove that any of the hoods provide any gains in airflow or cooling. You'll see some anecdotal evidence about the ability to feel heat coming out and things like that but I've never seen anyone actually post data logs pre and post hood swap to back up their claim. I monitor my intake temps pretty religiously and even with an open air filter and a hood that allows for no more air over stock my truck is usually within two to three degrees of ambient at intake one. the stock hood is generally half as heavy as the aftermarket cowl hoods unless you get a carbon fiber and then the difference is still a few pounds lighter
 

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Hey Ken, I have a red 99 with the stock hood. I have been considering changing to a cowl hood. If it is something you may be interested, shoot me a PM. I live in Raleigh.
 

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a cowl hood is an intake vent .. not an exhaust vent

air pressure at the base of the windshield while driving forces air backwards into the cowl opening .. this has to prevent any real exhausting of hot air unless parked with the radiator fan turning

drive a cowl scoop in the rain and watch the water drops get sucked in ..

or tape one end some little strips of yarn along the edge.. they will get sucked in to

if you want to exhaust engine compartment heat you need a vent that relieves the under hood air pressure but you can't do that while venting to a high pressure area like the base of the windshield

de-cluttering the engine compartment so the air coming in the front end can get through and out down the firewall and under the truck more easily would probably do more
 

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Wile E. Coyote, Super Genius!
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I put a cowl hood on a Firebird years ago. Until I put a sheet metal pan with foam around the edges on the carburetor, it exhausted air out the cowl. I did the strip thing, the strips always blew out the back of the cowl. Airflow coming in the radiator, getting heated up, and exiting the cowl, especially with a clutch fan. may exceed the pressure buildup at the base of the windshield. However, once I put said sheet metal pan on the carb, with foam that sealed to the hood, then it was an ingress. It was a fiberglass hood scoop on a metal hood. Once I did the sheet metal pan, I had to reinforce the cowl, as it kept getting all puffed up, like it was going to rip itself off the hood. Didn't do that without the cowl being sealed off from the engine bay.

The highest pressure air on a vehicle is right at the tip of the nose. This pressure coming in the front is likely higher pressure than the air at the base of the windshield. It's why motorcycle manufacturers always place their ram air scoops at the very front of the fairing.
 
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