That’s what I was wondering about the air going into the grill if you seal the air cleaner to the hood and air over the surface creates a low pressure zone at the scoop opening wouldn’t the carb have to overcome this and effect performance?
Plenty of cars came factory that way and ran plenty good. Not sure how effective it really is other than dropping intake air temps.
Yes, my 72 Mach I has the NACA hood with Ram Air so I’m familiar. I’m just thinking by the time you cut a hole in the hood & come up with some way to seal the air cleaner to hood you’ve spent time and $ for little or no gain. All I have to do for my cold air intake is cut a couple holes in the inner fenders.
It actually goes out the back of the compartment and under the car. The air coming from the front under the bumper causes a lower air pressure and the air flows to that.
I've never checked for air flow in or around the scoop. Some great ideas here on the thread for doing just that. I saw the paper flag test being performed in the movie Ford vs Ferrari. Just so readers are aware, the second photo in my posting is when I had a 351W installed with an Edelbrock Air Gap, 1" spacer and drop bottom air cleaner. The air cleaner sits up pretty high in the scoop. Not so much with the 302.
F vs F was how they use to do it before expensive wind tunnels became available in the 80s. 351W is already taller just because of the engine itself. 351W with a Pref barely fits. Bill Elliott beat up all completion pretty bad for a few years in the 80s. Then they found out Ford was giving him wind tunnel time to get those extra MPH everyone else wasn't. Just shaving the the "drip rail" off the top of the car is worth 3-5 MPH. Mirrors, wipers, etc all increase wind drag and reduce speed, or you have to increase HP to get the same speed. NASCRAD caught JJ cheating during pit stops when pit crew would pull the tire fenders out when they hadn't even been touched. Found out it decreased wind drag due to tunnel testing.
Very nice. Could you please tape some string on the front of the hood to check what the air actually does at different speeds? Inquiring minds want to know
My Comet had a hole already cut in the hood when I got it. It allowed me to use a carb spacer and air filter that slightly slicks out of the hood but still tucks under the scoop. I believe it not only allows for cooler air flow but also helps underhood heat escape when parked. Might try testing it.
I did that once on a 82 Zephyr I put a 460 in. Put a temp gauge under the hood with it ran under the wiper blade to hold the gauge in place. At stops, boy would the temp climb fast. just a few MPH for air flow, and it would drop fast. You could even tell when the fan kicked on.
Someone mentioned earlier that there is no problem with rain coming in the scoop. That's because almost no air comes in either. I've had a hole in the hood under my Mustang scoop for almost 50 years, nothing much goes in there. If you look at the front of a Maverick hood there's an angle that causes air to flow upward over a scoop that has the opening on the hood surface. To catch that air the scoop opening needs to be several inches above the hood surface. I think it does help a little with cooling under the hood, especially when parked.
NASCAR mechanics studied this to find the best place for cooler air from the hood area. They found the base of the windshield is the highest pressure area in the hood/windshield area. That's why your vent pushes so much air when you open it. Ford also studied it and found until you get 100MPH+, there is no air being forced into a hood scoop. Main reason the Thunderbolt used the headlights, and the Fairlane "R" code ones had the scoop opening at the very front of the hood to catch the air. A sealed airscoop to the carb, will give you cooler air from the outside area, but only because it doesn't allow under the hood air to get into the carb opening. Cooler air is always better.