Mopar cold air intake - do I Have to cut

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edodo

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oh that sucks....im glad i diddnt get it even more now...they just changed the intake location and not the actual filter/system
It's an air filter you can wash,instead of replace.
Not sure if it's better or worse 🤷‍♂️
 

BrntWS6

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I Was following you install and it gave a lot of info. THANKS.
When you cut the hood do you need to change anything in the inside to get the air from the hood cut instead of the front grill ?
Also , the Air Filter as I was reading is worst off road then the OEM paper filter. witch one do you use ? I saw you can change between them.
Thanks a lot man
No, there is nothing to change under the hood to redirect air.

I use the filter that came with the CAI. But I do not do any off roading.
 

mgarciaknight

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When you cut the hood do you need to change anything in the inside to get the air from the hood cut instead of the front grill ?

How exactly do our 3.6L breathe? I changed the air filter yesterday and realized the entry to the air box is rubber sealed to the back and motor side when the hood is closed, which leaves the front side and outer side. Outer side seals itself with the shape of the hood. On the front side there is no direct current or plastic dam that directs flow into the box. The grill is no where near there. The front side entry is behind the headlight and other plastics. So again, how exactly do our engines breathe? How is air directed toward the front side opening and into the air box?
 

roaniecowpony

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When you cut the hood do you need to change anything in the inside to get the air from the hood cut instead of the front grill ?

How exactly do our 3.6L breathe? I changed the air filter yesterday and realized the entry to the air box is rubber sealed to the back and motor side when the hood is closed, which leaves the front side and outer side. Outer side seals itself with the shape of the hood. On the front side there is no direct current or plastic dam that directs flow into the box. The grill is no where near there. The front side entry is behind the headlight and other plastics. So again, how exactly do our engines breathe? How is air directed toward the front side opening and into the air box?
I just went out and looked at what you described. The inlet of the airbox is not "sealed" to the hood. It has a soft rubber flap on the duct that contacts the hood on 2 sides of a rectangular shape. The front side of it is open. If you look behind the bumper, in the fenderwell, there is an opening in the sheet metal where air can flow in and up to the airbox inlet. It's a crooked path, but it's definitely the largest path to the airbox. Air can also flow in through areas behind the headlight and more to the center, but those are much smaller paths. It's not ideal, but its enough for this engine at it's stock rating.

The D shaped hood style CAI is a cleaner path and may provide more airflow. But the question is: Does the otherwise stock engine actually make more power with this modification? Maybe yes, maybe no. There are just too many variables to be able to armchair analyze it with any validity. Testing it is the only sure way, IMO. Real, 0-60 or 1/8 or 1/4 mile times or other acceleration tests are the only methods I know of that mean anything. Seat of the pants is way too subjective.
 

mgarciaknight

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I just went out and looked at what you described. The inlet of the airbox is not "sealed" to the hood. It has a soft rubber flap on the duct that contacts the hood on 2 sides of a rectangular shape. The front side of it is open. If you look behind the bumper, in the fenderwell, there is an opening in the sheet metal where air can flow in and up to the airbox inlet. It's a crooked path, but it's definitely the largest path to the airbox. Air can also flow in through areas behind the headlight and more to the center, but those are much smaller paths. It's not ideal, but its enough for this engine at it's stock rating.

The D shaped hood style CAI is a cleaner path and may provide more airflow. But the question is: Does the otherwise stock engine actually make more power with this modification? Maybe yes, maybe no. There are just too many variables to be able to armchair analyze it with any validity. Testing it is the only sure way, IMO. Real, 0-60 or 1/8 or 1/4 mile times or other acceleration tests are the only methods I know of that mean anything. Seat of the pants is way too subjective.
I stated it seals the REAR and MOTOR SIDE, pnot the entire thing. I mentioned the outer side and front are open. Here are pics of what I am saying. But if it was designed so we can get more direct air in, wouldnt it be better than limiting to nooks and crannies for air?

09AE4B92-0BC7-40F6-BAF6-127DB66EC904.jpeg
6693B5E3-F63A-48FA-B483-A3735F2B1FF0.jpeg
F66DB9C2-8EEC-4C6F-9A7A-EEC1CF3E4F70.jpeg


I just went to look at the openings you mention but they are so restrictive. And the spaces around the headlight are so tight.
 

roaniecowpony

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I stated it seals the REAR and MOTOR SIDE, pnot the entire thing. I mentioned the outer side and front are open. Here are pics of what I am saying. But if it was designed so we can get more direct air in, wouldnt it be better than limiting to nooks and crannies for air?

09AE4B92-0BC7-40F6-BAF6-127DB66EC904.jpeg
6693B5E3-F63A-48FA-B483-A3735F2B1FF0.jpeg
F66DB9C2-8EEC-4C6F-9A7A-EEC1CF3E4F70.jpeg


I just went to look at the openings you mention but they are so restrictive. And the spaces around the headlight are so tight.
That area where your red arrow is, has so many paths to it that it clearly is enough that the engine makes its rated power in an unmodified engine. Will it make more horsepower if it had more air flow to that inlet? I dunno. But just popping the grill off and driving it might be a good test.

With so many apps and OBD2 devices out there that have performance (0-60, 1/4 mile, etc) functions, it should be a simple test and one that could be done back to back in the same environmental (temperature, humidity, pressure) conditions. I have one of those created by Palmer Performance called Dash Command. I'd do the test myself except my issue with what I suggested about removing the grill is that my winch is butted against the grill. I'd have to loosen the aftermarket bumper to remove the grill. DashCommand B - YouTube
DashCommand - Palmer Performance Engineering, Inc.
 

roaniecowpony

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This thread reminded me of the MotorTrend channel show "Engine Masters" I saw last night. They had an engine on the dyno that produced something like 560hp with open headers. Then they put a full exhaust on it with baffled mufflers and over the axle pipes with terrible "squash" bends, then tested again. It produced ~545 hp. Then they put straight thru mufflers on it and it produced exactly the same hp. Then they took off the mufflers altogether and put just some nicely mandrel bent over the axle pipes on it. Virtually the same hp as with the first muffler setup and bad bends.

They had a bench racing session to analyze what they saw. The engine was cammed a very mild stock type profile. They all agreed that their experiences told them that a bigger cammed engine would have seen much bigger differences in (hp) with the exhaust flow changes. Sometimes more isn't always better by itself. But if you had other modifications, say a hotter grind cam, more air in or exhaust out, might be a big deal.
 

mgarciaknight

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This thread reminded me of the MotorTrend channel show "Engine Masters" I saw last night. They had an engine on the dyno that produced something like 560hp with open headers. Then they put a full exhaust on it with baffled mufflers and over the axle pipes with terrible "squash" bends, then tested again. It produced ~545 hp. Then they put straight thru mufflers on it and it produced exactly the same hp. Then they took off the mufflers altogether and put just some nicely mandrel bent over the axle pipes on it. Virtually the same hp as with the first muffler setup and bad bends.

They had a bench racing session to analyze what they saw. The engine was cammed a very mild stock type profile. They all agreed that their experiences told them that a bigger cammed engine would have seen much bigger differences in (hp) with the exhaust flow changes. Sometimes more isn't always better by itself. But if you had other modifications, say a hotter grind cam, more air in or exhaust out, might be a big deal.
Yes I remember that show. Its funny how air will always find a way.
 

Altitude2020

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Do you have to cut the hood for the Mopar CAI. I will be towing a trailer and I feel more air would be good. But I don't want to cut the hood. We have rainy , snowy weather here and the cover would be on most of the time.
 

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I don't like how the design of the Mopar CAI puts the hood opening parallel to the flow of air instead of perpendicular to it. Since as the velocity of an airflow increases, it's pressure decreases, doesn't the airflow moving across the surface of the CAI's hood opening create a low pressure area instead of a preferable high pressure area?

I'm thinking I would be better off installing the cut out towards the back of the hood as a heat vent.
 
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BrntWS6

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Do you have to cut the hood for the Mopar CAI. I will be towing a trailer and I feel more air would be good. But I don't want to cut the hood. We have rainy , snowy weather here and the cover would be on most of the time.

You don't have to. I only use the rain blocker during downpours. It's off 99% if the time. I have checked it many times and even in moderate to heavy rain the airbox is dry.
 
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