How much horse power are you making through a 6 pack / shaker type air cleaner assembly.
Is there a noticeable hp loss?
I was looking to use this on a 2x4 Hemi.

I never measured it but the seat of the pants feel was big

In the 70's I was at a Mopar sponsored test and tune before the Winterntionals. Dave Boertman was there with his Challenger. The Mopar engineers were testing the shaker. They concluded the shaker hurt the cars performance. If you have a Challenger run the TA hood like all the Stock Super/Stock cars do. If you have a Cuda good luck AAR hood doesn't work either just a weight reduction.

This is second-hand information, but I've heard 3-4 hp better with a Shaker, and 6hp with the T/A hood.

The only hood that made power was the original A12 six pack hood. Designed to catch air above the boundary layer.

There are a couple of ways to take the OP's question. Is he asking about how much the element will flow? Or is he asking about the scoop above the hood?

Not sure about that.

The T/A scoop sits above the hood too. But not as much.

Also the 72-up a-body twin snorkel scoop sits above hood some. But it’s not connected to anything, not as high as T/A, and smaller inlet cross section.

The top of the 68 super stock scoop is at least as high as an A12 scoop.

My A12 base made more horse during dyno with filter and lid .. FWIW

Hey guys first of all Thanks for the replies. Sorry I'm just getting back to this snow is making it busy for us.

I guess my actual question is more about the air cleaner assembly and not about the scoop. This will be used with 68 SS scoop so there will be some fresh air to it ( may or may not be sealed to hood).

So what I was asking is if anyone ran higher HP through this setup and was it noticeably restrictive.
I will be using it on a 528 Hemi w/efi.

My 540 Hemi makes almost 700HP with a 1050 Dominator under a Shaker. So yes, the element has some good flow.

And it is well worth it to go to the trouble of sealing it to the hood so that the engine is getting ambient air.

Most air flow and hp would be found in the Fram C332V, the mesh is open and flows a fair amount (bottom photo).

The OEM and reproduction version are half covered in metal and by looks would flow 30 to 40% less than the 332V. They look great on a restoration, but personally I use the C332V for more power, but put the reproduction in when the car(s) are parked or at a show.

If the question is "how does this compare to a round element?", you can stack two six pack elements in there for more volume.

You can always grab high pressure air from the cowl like this.

I would love to see some testing data from inside that air cleaner with the hoses hook up at 60+ MPH and above compare to no hoses.
The reason being is the airflow over the top of a flat hood going up and over the windshield may make a vacuum over the vent in front of the windshield, not high pressure. I'm basing my thoughts on seeing pictures of a Mopar test car at the 1/4 mile finish line with thin narrow confitti type paper test strips tape onto the car, they wanted to see what the air flow was doing in real time and racing conditions. I think this was a 10.0 to 11.0 second car along time ago

Ever open a fresh-air vent in the car while going 60 ?
Plenty of fresh air gets into a cowl vent.
Not enough to be called "ram air", especially as it doesn't have a straight path.
For that, you need to get above the boundary layer or use the front of the car.
Might pick up a small wind-chill factor, depending on ambient temp.

It seems that I see this subject a bit different than some here. I am not sure that 'ramming' air to the carb is the intent or even a good idea. Any air disturbance at the carb throat is not good. The carb wants smooth, cool air to deal with. So the objective is to have ambient temp air available to the carb rather than the heated engine compartment air. As long as the scoop allows the carb to draw the cooler outside air as it needs it with no delay, restriction or disruption, it is getting what it needs.

Now, if there is some distance to the cooler air source or if the ducting is warm enough and long enough to heat up the incoming air, then some pushing to clear it might help. But, it seems that any scoop mounted directly above the carb and that allows the cooler ambient air to be drawn straight into the carb is the best thing. Air cleaner elements not only filter the incoming air, but also stabilize the air stream. Or straighten it out, so to speak.

When playing around with my Cuda a few years ago at the track, I found that the first pass of the day would be about the same E.T. whether I had under hood air or fresh air at the carb entrance. The E.T. with outside air was a little better, but with a barely warmed engine, the E.T. was close. But with each successive pass, as the engine compartment got warmer, the difference became more pronounced. The biggest difference was 1 1/2MPH between under hood air and fresh outside air. Obviously, a big difference.

Maybe Dom or some of our other carb gurus will chime in with their expertise.

Interesting info, Cab. I remember seeing videos of old films showing the airflow coming up and over the center of the hood clearing the scoop intake, crashing down at the cowl and then being forced up the widshield. Pretty sure that's why the cowl induction hood was designed the way it was, but I'm a laymen on this stuff.

I do know that as mentioned above, that the air pressure that comes out of my fresh air vents is impressive, AND when I have them open, my grandsons love the sound of the intake noise when I hit wide open throttle. They are always yelling out, "Punch it Papa", so they can hear the intake rush.

Is the A12 assembly the same as the 6PK air cleaner assembly?

In one of the old Direct Connection Racing Manuals I have (plain paper with a staple holding it together), it stated the most effective scoop they found was 1) the A12 Superbee/RR, 2) the T/A Challenger followed by the Shaker and AAR respectively...I’ll have to see if I can find it, was from the early 80’s...

No, they where way better due to being seal to the lift off hoods with the bigger and taller six pack scoops
I bought a fibreglass replica A12 air cleaner base from Year one to use on my Duster six pack motor with a 1968 SS Hemi scoop molded onto the hood

I know that the six pack air cleaner housing without any changes can flow enough to get a 69 GTX to 11.0’s running in stock appearing. Somewhere after 11.0’s the housing becomes an issue. I know when they get down in the lower 10’s the housing is an issue that needs to be addressed. My unsilenced 68 340 housing was an issue and I’m running high 11’s. The AFR would just start going lean about 6200 rpm. Modified the housing base and AFR are rock steady as high as I have the guts to go. If your hemi is a serious effort you can outflow the housing. There are quicker 6 pack cars, I’m just not sure if Bryan or the others are running untouched housings.