Air flow through hood scoop

[Badger]

Lew Ledyard is the brightest guy on this thread. The front of the scoop is a LOW pressure area! Air exits the front of the scoop! The smart thing is to run the scoop reversed, with the opening near the windscreen where the pressure is higher. Doesn't matter what the original Cobra team guys did..those guys made a lot of mistakes but didn't change simply because it "looked" right. Peter Brock

[mr0077]

Badger, you're probably right (about the front of the scoop being a relative low pressure area - the base of the windshield is definitely a relative high pressure area), but someone should do a "tuft" test to check that out (tape 1 or 2 inch long pieces of yarn or string onto the leading edge of the scoop and watch it while driving to see which way air was going at the scoop). Obviously having a turkey pan with a hood seal would affect the results due to engine air flow, and I suspect that there are a whole lot of other variables that could affect it...whether the cooling fan was on, is the radiator sealed to the body, is the radiator upright, etc.

[Anthony]

Originally Posted by Badger

Lew Ledyard is the brightest guy on this thread. The front of the scoop is a LOW pressure area! Air exits the front of the scoop!

Originally Posted by mr0077

but someone should do a "tuft" test to check that out (tape 1 or 2 inch long pieces of yarn or string onto the leading edge of the scoop and watch it while driving to see which way air was going at the scoop). Obviously having a turkey pan with a hood seal would affect the results due to engine air flow, and I suspect that there are a whole lot of other variables that could affect it...whether the cooling fan was on, is the radiator sealed to the body, is the radiator upright, etc.

With my car, you can see streaks of oil on the underneath side of the scoop going foreward, out the front of the scoop. My take on it is that the air coming through the radiator opening (after warming up) pressurizes the engine compartment, of which a portion exits out the scoop. So, if you nail the throttle, if you don't have a good seal on your turkey pan, not only are you getting low pressure air, but it is warm air as well, both decreasing engine HP. If you seal the turket pan to the scoop, at least you will get cooler air.

[Lew Ledyard]

Originally Posted by Badger

Lew Ledyard is the brightest guy on this thread. Peter Brock

My wife would so beg to differ.