I found this article interesting :
https://www.dragzine.com/tech-stories/engine/high-speed-engine-tuning-factoring-ram-air/

Worthy read with a lot of repetition IMO

"Conclusion

The effects of ram air at high speeds can cause considerable boosts in power or unexpected complications. Taking into effect engine performance at higher speeds becomes complicated at times but can mean the difference between a screaming run and a surprise slump."

i seem to remember warren johnson quoting how much hp it took pushing a scoop through the air

I wonder how much that is in comparison to how much H/P the whole frontal area of a typical door slammer type car takes ? The trade off may be worth it

Funny you mentioned this, cuz I was wondering if I should try something like that in my fresh-air baseplate; the new scoop is so freakin' big that it's gonna trap some serious air (second-guessing myself on having gone so much taller than original T/A)

The original Chrysler hoodscoops, like the 6 pack scoops, were fully open under the scoop and had an air filter base to seal all around the large oval air cleaner. If you copy that design by adding a carb base plate pan and the foam to seal it to the bottom of the hood if should be ok as more air has a chance to move down below the hood line rather than swirling around up top building up pressure. Having a big scoop and only a small air hole for the carb inlet or a smallish round air cleaner opening you may be trapping more air inside the scoop than the engine can use on the top end.

That would mean that you are creating a positive pressure or a Ram Air effect, if you can tune for that you will theoretically, make more power. According to folk more experienced than I, a typical design of pro stock scoop will generate 2 psi @ 200 mph. That is 1/7 or 14% more "potential" power if tuned for.
I have no idea how much pressure a usual fwd facing mopar scoop will generate at more moderate (140 mph) speeds, I intend to data log the pressure at the rear of the scoop next season and also reference the fuel pressure regulator to the same. Pretty sure something is happening as we do tend to drop around .4 AFR at the stripe, the caveat is I don't have enough data to prove if this attributable to the scoop or not.
My

Yes that is good. but also too much pressure can cause the hood scoop to fail at some point, especially the ones that have been added to a flat hood. Pro stock cars may use carbon fiber hoods and scoops, which if that is the case would be stronger than fiberglass that bracket racers use.

This is true, I had an unsealed glass hood with a small, 3" high six pack scoop. I only had 4 pins on it (2 front, 2 rear) and it used to lift in the middle at speed. I don't know if this was the scoop or just normal airflow through the front that caused this

Years ago I hung out at the top end of our local track and watched the cars go thru the lights instead of watching at the starting line like I normally do. The cars that went over say 120 you could see on some cars with 'glass hoods that the air was pushing the hood up or down a noticeable amount. One guy had a purple 70 Challenger and the front middle area of the hood would lift up a bunch. He really needed to block off the grill opening with some clear lexan like some do, or add another pin in the middle as it was flexing the hood way more than I would be comfortable with.

Both my AAR hood (fiberglass) and my home made carbon hood have been held with 4 pins. Hood doesn't move at all at close to 150.
Doug

The hood I had at the time wasn't the best available, it was a MAS one (1990's). It was eventually much modified and thus became really heavy, ended up with 8 pins. We have a nice lightweight flat hood with a hole for the T/R now and a clear makralon scoop.

I had to use 4 Dzuz fasteners in the front of my fiberglass hood with a 1968 Race hemi type scoop made with the hood and four on the rear by the firewall and two more on each side to get it to not move around an distort above 100 MPH

I was always rather amazed at this photo...

Big scoops act like a parachute at speed. If the engine cant use all that air, its trapped.

Good article “ON ALL cylinders ” about this very topic. According to the article, it’s a wash. the horsepower gain is equal to the loss, created by drag, of the scoop.

Can you post up a link ?
TIA.

Edit: Found it

https://www.onallcylinders.com/2015...he-science-behind-hoop-scoop-technology/

My car did that at 1000ft , the middle area of the hood would lift up a bunch. The bracing separated from hood skin.

A worthy article to read.
But one question the article does not address. It is of course well accepted it takes horsepower to push an air intake scoop along at speed. And the claim in the article is the horsepower gain from any ram effect at speed is offset by the aero drag of the scoop. This is of course on this point ignored the at any speed the benefits of effectively cold intake air gains observed.
My point here, in reality the car itself is effectively "drafting" behind the scoop, and reducing therefore the cars drag contribution, and that benefit is not addressed directly in the article and makes me wonder if overall the drag vs ram effect is indeed really a "wash".

ET is the definitive proof of concept.