Turn r/t hood into cold air intake?

[Tonker1]

Hey, I'm a proud owner of a 73 Challenger and I want to make some improvements to the air intake system without performing modification to the exterior of the car. So I've been looking at the r/t hood on the challenger and thinking there's a lot of potential to set up a direct cold air intake system from the inlets on the hood to the air cleaner; does anyone have any ideas on how to go about doing this or know of any aftermarket parts to assist in this project?

 

[ROCKY ROCHE]

just remove the insert blocks, and let the dual snorkle do the rest

 

[burntorange70]

You could do it but I don't know that it would work all that well to bring in air. That hood was made just for looks. I would look in to another scoop that was made for fresh air.

 

[ramenth]

just remove the insert blocks, and let the dual snorkle do the rest

I think the idea would be to seal it off to the air cleaner, like an Air Grabber or Shaker.

It can be done. I've been working on making such a set up for my Ramcharger using a twin bulge 'Cuda hood skin, oh, for about forever now.

 

[74 challenger]

it can be done if you know a ac/heat duck installer.they can fab up just about anything.just like making a air grabber for a 6-pak set up. let us know what you end up doing please.

 

[Chryco Psycho]

the Chall hood is actually open unlike the Cuda hood , once the inserts are removed it still looks blocked but it has a rain trough to take the water out into the hood frame

 

[challenger6pak]

Several years ago I considered the same idea of using the Challenger scoops for ram air. My buddy that is an engineer mathamatically figured out that the CFM through the scoops would not be enough for a modified 440. I never investigated it after that. The rain troughs are riveted in place they can be removed also.

 

[Tonker1]

The plan?

So here is the plan so far
1. Cut two sections from air cleaner lid(blue)
2. Build up surrounding area with soft structural rubber (black)



3. Probably cut off and seal over snorkel on cleaner lid, maybe build door on snorkel in case driving in rain?

4. Build two tunnels out of fibre glass (grey)
5. Add rubber around tunnel-filter air hole (black)
6. Build bracing system (brown)



Would driving in heavy rain with a ram air intake cause engine problems? Any experiences to share from people who have ram air would be great.

Suggestions, improvements, hints and any general advice would be much appreciated,
Thanks

 

[Juan Veldez]

First off, I have the same hood on my Challenger and thought the same thing, why not make these things functional instead of decoration. I wouldn't do this if you think you are going to get "big" horsepower gains or much better fuel mileage by the way. So here are my thoughts:
1. challenger6pak brings up a good point. Does the open area in the scoops alone provide enough air during wide open throttle? Pro Stockers have this down to a science. But, backyard engineering on my part says that based on the original air cleaner snorkel hole size, it would be similar. But don't some of these have two snorkels? That's probably the best bench mark to go by, not the single. Obviously you do not want less air available than stock as you probably have made motor changes that now creates more horsepower which requires more air.
2. Heavy rain would probably be a problem as the filter will get saturated after a while. I recommend a least a rain gutter/downspout type configuration be designed to capture water running in at the bottom of the tunnels or maybe something at the bottom of the air cleaner (outboard of the filter) that can capture water and direct the it away from engine (water heater hose as the downspout for example). Water vapor will still get by though and again eventually saturate the filter. I assume you will still run a filter at least while street driving. And removing it at the drag strip really doesn't help all the much anyway. At least not worth the risk. A little water injection won't hurt the motor per say. But your not going to be going balls out in a rain storm anyway, I hope!
3. I assume you would sell or keep this original air cleaner and modify an aftermarket one?

My plan was to just leave the plates that block the scoops out and use an aftermarket air cleaner that has the filter assembly on the top. I'm in California and can easily decide not to drive mine in the rain. But I would carry foam inserts that could be inserted in the scoop holes in case I was surprised. You could also do the foam inserts, but you would have to have a secondary approach to allow dry air into the air cleaner if you plugged the scoop holes during a rain storm. Or park under a bridge and wait it out like I did when I had 2 exposed paper air cleaner filters exposed hanging on top of the 6-71! Good luck, I like the overall idea!

 

[Tonker1]

Don't worry, I wouldn't dream of modifying the original cleaner, I was planning on picking up an aftermarket cleaner lid without the snorkel from yearone.
1. To further the rain concept, build a hinged sealable door onto the side of the air cleaner baseplate, so once foam inserts have been placed in the scoops the engine can still breath!
2. Also a support framework will probably be necessary under the cleaner baseplate to take the uneven (forward tending) load off the carburetor.

Thanks heaps Juan, that's the sort of input I was looking for!

 

[challenger6pak]

It looks like you have the air cleaner with the vacuum operated flap which allows more air flow than the single snorkel. If it were me, I would open the scoops and leave the drain troughs in place. I would open the scoops just to allow more air flow under the hood. It does help with under hood temperatures. Then I would buy the ram air, sealed air cleaner system that uses scoops under the front bumper or under the front of the car to bring in fresh air to the engine. This would save time, headaches, possibly money and it would work for sure.

 

[Joe's Challenger]

Tonker, I like this thread and i didn't know the inlets were not functional- I am building a 440 in a 73 Challenger so I want the same results. I say this not to insult ANY MOPAR fans, when I did my 68 Camaro I created a cowl induction kit with a 16" cake pan and a aftermarket rubber seal attached to a drop plate that brought fresh air in from the windshield.

So my question could you do something similar to that- open the back of hood, fab a air channel into the hood that opens over the intake? I think I will look at this more, I like your ideal and hope you keep posting to what you find.

 

[ramenth]

Tonker, I like this thread and i didn't know the inlets were not functional- I am building a 440 in a 73 Challenger so I want the same results. I say this not to insult ANY MOPAR fans, when I did my 68 Camaro I created a cowl induction kit with a 16" cake pan and a aftermarket rubber seal attached to a drop plate that brought fresh air in from the windshield.

So my question could you do something similar to that- open the back of hood, fab a air channel into the hood that opens over the intake? I think I will look at this more, I like your ideal and hope you keep posting to what you find.

How dare you post that %**^ here!

Nah, just kidding.

You mean something like this?

View attachment 6938

View attachment 6939

That's the air box I've built for my M-body. Still need to skin it and build the support structure.

Personally, I'd like to see more of challenger6pak's engineering buddy's results, too, and see what the air flow coming through the holes would be at speed under WOT.

Especially considering that low lying hood scoops have a tendency of not really "scooping" air. The air flowing over the hood doesn't really flow into the hood. Even the Shaker had it's drawbacks in this area.

One of the reasons AMC designed the S/CRambler scoop like this:

View attachment 6940

People may think it looks funny but it actually is up in the air stream.

 

[moparleo]

Personally before I would go through all that trouble I would use what the Mopar engineers came up with on the Trans Am program, Can you say " T/A " ? Much money spent with actual aerodynamic studies that showed that unless the intake scoop is raised above the surface of the hood high enough to get above what is called the "boundary layer " which is the air flowing over the skin of the hood, the opening has to be raised above the surface enough to get " clean " air which just means non turbulant air. Cowl induction works by drawing in cooler air from the low pressure area at the base of the windshield and rear of hood. A reverse scoop if you will. Remember the Power bulge type hoods were designed by stylists and not by engineers. All show and no go. Older guys will remember the backwards teardrop hoods of the sixties ,factory on the performance model Comet and snorkel hood scoops of the early seventies Pro Stock cars. Proven to draw more air with the opening facing the backwards than forwards..The T/A hood is also quite military looking, like the intakes of old fighter planes. Function. Cool air delivered to the engine by either the low pressure method or high speed ram method. Really both types not very efficient except at high speeds, like the wing on a Daytona or Superbird.

 

[Joe's Challenger]

Mopar leo, thanks for the info, I seen the TA snorkle style hood, but I cant seem to fine an aftermarket that reproduces the hood, and it makes sense the effects are better at high speed. Cosmetically looks good, not practical for street crusing. With that being said the Cuda T/A hood has a very sharp hood, would this hood fit the Challenger? Thanks Joe

 

[moparleo]

The Cuda AAR hood will not fit the Challenger's. The Challenger hood extends all the way forward in one piece. The Cuda hood has about a 4 " header at the front of the hood. The T/a hood is available from Year One and I am sure there are others on the web. They sell in the $700-750 range are are made of fibreglass.

 

[challenger6pak]

The Cuda hood will fit the Challenger. You have to glass an extention to it of add the Cuda header panel between the Challenger fenders. Again, why bother. As for the engineering results they are gone. Much of my Mopar stuf was destroyed in the 2005 hurricanes. I lost original assembly line photos etc. They all were in zip lock bags. Even so after being under water for a while they leaked. I agree with usong the stock hoods. The T/A hood is the best design for the Challenger.