Opening Hood Scoops=Better Cooling?

[Ricks72Chlgr440]

The hood scoops on my 72 Challenger are blocked with the original black plates. Is there any benefit to opening those to let hot air out while sitting in traffic? I know my newer 2021 Challenger has several hood vents to let hot air out. Just wondering.

 

[Xcudame]

I would think opening them up like you suggest would let some hot air out. Any amount of hot air coming out has to be better than none. Try and see if you notice a difference.

 

[heminut]

I never noticed any difference after I did it to my first 70 Cuda. I didn't even mess with them on the Cuda I have now, I regard it as a wasted effort. BTW, I live in the desert southwest.

 

[Challenger RTA]

I think I read that the scoops where to low of a profile to function. Below the the air steam. Something like that. The underside of the hood looks as if there might have been a plan to do some sort of fresh air application. Now the T/A and AAR hood is a different story.

 

[Xcudame]

Yes, the scoops are why to low to force air in. And it sounds like they don't do much for letting hot air out per Heminut!

 

[pschlosser]

Over the years, this has been tested more than once. I seem to recall the conclusion was as @Challenger RTA suggests, the scoops are too low, within the turbulent slipstream along the surface for there to be any real passive benefit to opening those up.

We're talking about passive cooling and horsepower gains. It is our hope, opening those scoops allows air to passively flow inward to the engine compartment as the vehicle moves down the road, and carry heat energy away from the motor as this air passes over the engine, is heated, and flows downward and out of the compartment. Or, by pushing heated air around the engine away, and replacing it with cooler air from outside.

But tests have not shown there is any measurable cooling to opening those up.

Were fans put in place, or were there a sucking force at those openings, there may indeed be increased air flow.

The shaker hood setup benefits by openings about the same size as those of the rally hood (once opened). But the primary benefit is a sucking force pulling cooler (than within the engine compartment) into the engine. The shaker hood does not provide much (if any) cooling affect to the engine. But the cooler air helps the induction system make more horsepower.

It seems possible those rally hood scoop openings may let in some cool air at higher speeds - cooler air that may be sucked in by the air cleaner. But I don't believe it is as dramatic an increase in power as the shaker setup, because I don't believe anyone has ever been able to measure an increase in power between a rally hood with open versus closed hood scoops.

 

[heminut]

I think I read that the scoops where to low of a profile to function. Below the the air steam. Something like that.

That's correct, they sit in what's called the 'boundary layer' and don't come into any kind of forced air situation because of it. I seem to remember reading somewhere back in the day that hot engine air was actually PUSHED OUT of the openings at lower speeds because of the lower pressure of the boundary layer as opposed to the higher pressure of the air flow above it and the pressure created in the engine compartment from the air flowing through the radiator and underneath the car!

 

[heminut]

Back in the day, this was considered one of the better factory hoodscoops!

 

[Xcudame]

I think we got side tracked and came full circle. OP Ricks72Chlgr440 asked if unblocking his hood vent would let hot air out at idle in traffic.

 

[heminut]

He did, and I stated that I noticed no difference in temps with my scoops open on my first Cuda.

 

[Xcudame]

Good! My second post holds true!

 

[Ricks72Chlgr440]

Thanks for all your input gentlemen!

 

[Challenger RTA]

XCUDA ME. My bad I have to own this. As XCUDAME posted : Something is better than nothing. In my opinion, with the front and rear hood seal in place there is nowhere for it to really go. Removing the blocking plate would only allow a minuscule amount of heat to escape. The back portion of the hood scoop would also be an obtrusion and would restrict convection flow, maybe even consider the flow from the engine fan.Having played with this idea both ways in the mid 70's.
Also a thought to install the the fender vent a ports from a 71 CUDA and make them functional. Being a mopar part. The 49 Buick Roadmaster might have been.

 

[Challenger RTA]

While were kinda on the subject. This is someones idea.I think it was in OHIO. I think a air grabber would have been a better choice. See if you can identify the other parts.

 

[Xcudame]

Does this win the "How to take a beautiful car and make it ugly" award?

 

[Mixup]

I had a cuda and challenger, the challenger hood scoop plates taking off open to the engine bay., the cuda hood plates taking off did not open to the engine bay the hood metal was still there cudas had no opening like the challenger

 

[heminut]

I had a cuda and challenger, the challenger hood scoop plates taking off open to the engine bay., the cuda hood plates taking off did not open to the engine bay the hood metal was still there cudas had no opening like the challenger

I don't know about the Challengers but the Cuda hood scoops aren't open behind the plates, they have to be cut out. And, as you stated, the sheetmetal of the hood would also have to be cut out. Cutting open those hoodscoops is not an easy job and once you do it you can't put the plates back in, there's nothing to bolt them to.