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Ive been searching and cant really find anything on this. I don't understand how a T/A with a cold air type of setup, plus hellcat light setup, plus functional hood scoop isn't worth anything in terms of hp. If that's the case, there's no point in ANYONE buying a CAI for their cars. Not to mention the T/A is a CAI plus more.

Any thoughts on this?

One theory I heard was that these cars are speed density, so a CAI won't make a difference because speed density won't compensate for the extra, and cooler, air like a Mass Air system would. That kinda makes sense. I've had over 20 yrs experience with the fox body mustangs and they were MAF cars.
 

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This is the perfect statement for those like me that thought that a Cai can increase hp.

Air Cooling: I've done many trials between OEM airfilter vs a CAI( and hellcat style front opening).
Summary : in a straight long drive CAI air temp is 3-5 °F higher than ambient while a OEM is 6-7°F. .
While in real daily drive with stops and lights the temp goes up much faster in the Cai system. So in a acceleration race from a stop a Cai Might delivery higher temp air which results in less HP.
In the highway also, i don't know how 1-2 °F can influence a performance.

My last thought on this is : for 300$ have a CAI is "cool" better view stuff to have with also a little deeper sound.
Would I buy it again? Probably not.
Actually Just in case of a supercharger.
Hope this helps

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Good question - and I have the same question about the 5.7L T/A versus other 5.7L Challengers. My car (stock other than a catch can) recently made 351 HP @ the wheels. Is that in line w/ other 5.7L Challengers or a bit higher?
 

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They get just about all they can out of these at the factory.
 
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The extra cooler air from the factory style units will give you some improved "drivability" in Summer months, but very little if any increase in HP. The variations of dyno runs are greater than what the HP increase are.


Aftermarket units are for "show", but don't offer any more "go"
 
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First post.

Ive been searching and cant really find anything on this. I don't understand how a T/A with a cold air type of setup, plus hellcat light setup, plus functional hood scoop isn't worth anything in terms of hp. If that's the case, there's no point in ANYONE buying a CAI for their cars. Not to mention the T/A is a CAI plus more.

Any thoughts on this?

One theory I heard was that these cars are speed density, so a CAI won't make a difference because speed density won't compensate for the extra, and cooler, air like a Mass Air system would. That kinda makes sense. I've had over 20 yrs experience with the fox body mustangs and they were MAF cars.

1. These aren't air-restricted MPG machines, the engines are making good power out of factory.


2. CAIs still need a tune, you can't just slap it on and and assume you'll get more HP.


T/A set up will run cooler than a Scat Pack and won't suffer from heat soak as quickly as a scat pack would, or so would be the theory.
 

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I did a ton of testing on my v6 NA and supercharged with cai's, what i found out, it was about airflow, not so much it being cooler, I'm sure some of this testing could bleed over to the v8 which I now have a srt 392. I used the same air boxes as the v8 on my v6 and tracking my airflow thru data logging there was airflow increases using cai/ filters and K&N panel filter over the stock filters even the hellcat filter.

I ran the hellcat filter and box set up when I was supercharged and I got airflow increase using the K&N filter. This showed at about 500 hp gross, the hellcat filter showed a restriction in airflow, dropping in a K&N panel filter i gained airflow which data logging showed this.

The few degrees in cooler temps some set ups show over factory your not gaining any measurable hp, it's coming from the extra air the engine is getting running a better system over factory.And if you think about it even more, the few degrees of cooler air your getting is being wiped out by the time it reaches the intake valve, how hot it is inside the intake manifold and heads.

I myself for my srt 392 I'm going to install the hellcat box (lower and upper) and install the K&N filter since I know even on a supercharged v6 making close to 500 hp gross the K&N filter showed an airflow gain over the hellcat filter. One has to remember it's not v6 vs v8, it's about hp, hp needs airflow whether it's being produced by a v6 or v8, being the 392 is around 500 hp there should still be a gain in airflow using the K&N flat panel over the hellcat air filter. I'm not chasing "cooler" air for hp, I look at airflow numbers.

I think most folks get to hung up on cooler air in these cai set ups, it's about airflow, not the cooler air making the difference, cooler air still matters, you still want to strive for the coolest air but don't count on it being the most important thing, your going to get more return on airflow and efficiency of the air getting into the engine.

You want to make it easier for the engine to take in air, using a filter that allows air to pass thru easier, whether it's a performance filter to fit in stock location or a larger filter with more surface area, there are other things that effect airflow- turbulence, some of your cai systems reduce inlet turbulence which helps increase airflow. So it's not so much about cooler air, it's about making the air more efficient to enter the engine where the power is coming from or potential to make more power.

I think most find swapping the throttle body's to ported throttle body's seem to help throttle response and even power, this is because a reduction in turbulence, smoothing the air flow, this is no different using cai's / performance filter's that help air flow efficiency.

I'll be testing all this later this year with some track testing, I'll run my car stock and baseline it, then bring it back home and change to hellcat air box (upper/lower) add the K&N filter, build a custom tube to connect my hellcat upper lid to throttle body, hand port my throttle body and also hand port my intake manifold. things that improve air flow efficiency. Not so much chasing cooler air. Just improving on how the engine gets the air. Car should run quicker even without a change in the tune, normally even a factory car runs a tad on the rich side at wot, so these efficiency changes should lean out wot and make a few more hp. this will show in trap speeds.

Worse case the car will run the same or a tad slower til wot tune is changed then get a good bump in power, more so than if nothing was ever done.
 

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I did a ton of testing on my v6 NA and supercharged with cai's, what i found out, it was about airflow, not so much it being cooler, I'm sure some of this testing could bleed over to the v8 which I now have a srt 392. I used the same air boxes as the v8 on my v6 and tracking my airflow thru data logging there was airflow increases using cai/ filters and K&N panel filter over the stock filters even the hellcat filter.

I ran the hellcat filter and box set up when I was supercharged and I got airflow increase using the K&N filter. This showed at about 500 hp gross, the hellcat filter showed a restriction in airflow, dropping in a K&N panel filter i gained airflow which data logging showed this.

The few degrees in cooler temps some set ups show over factory your not gaining any measurable hp, it's coming from the extra air the engine is getting running a better system over factory.And if you think about it even more, the few degrees of cooler air your getting is being wiped out by the time it reaches the intake valve, how hot it is inside the intake manifold and heads.

I myself for my srt 392 I'm going to install the hellcat box (lower and upper) and install the K&N filter since I know even on a supercharged v6 making close to 500 hp gross the K&N filter showed an airflow gain over the hellcat filter. One has to remember it's not v6 vs v8, it's about hp, hp needs airflow whether it's being produced by a v6 or v8, being the 392 is around 500 hp there should still be a gain in airflow using the K&N flat panel over the hellcat air filter. I'm not chasing "cooler" air for hp, I look at airflow numbers.

I think most folks get to hung up on cooler air in these cai set ups, it's about airflow, not the cooler air making the difference, cooler air still matters, you still want to strive for the coolest air but don't count on it being the most important thing, your going to get more return on airflow and efficiency of the air getting into the engine.

You want to make it easier for the engine to take in air, using a filter that allows air to pass thru easier, whether it's a performance filter to fit in stock location or a larger filter with more surface area, there are other things that effect airflow- turbulence, some of your cai systems reduce inlet turbulence which helps increase airflow. So it's not so much about cooler air, it's about making the air more efficient to enter the engine where the power is coming from or potential to make more power.

I think most find swapping the throttle body's to ported throttle body's seem to help throttle response and even power, this is because a reduction in turbulence, smoothing the air flow, this is no different using cai's / performance filter's that help air flow efficiency.

I'll be testing all this later this year with some track testing, I'll run my car stock and baseline it, then bring it back home and change to hellcat air box (upper/lower) add the K&N filter, build a custom tube to connect my hellcat upper lid to throttle body, hand port my throttle body and also hand port my intake manifold. things that improve air flow efficiency. Not so much chasing cooler air. Just improving on how the engine gets the air. Car should run quicker even without a change in the tune, normally even a factory car runs a tad on the rich side at wot, so these efficiency changes should lean out wot and make a few more hp. this will show in trap speeds.

Worse case the car will run the same or a tad slower til wot tune is changed then get a good bump in power, more so than if nothing was ever done.

I'm looking forwards to your updates, I like the way you get things done and the way you do it and I am fascinated by your next experiment being a SRT owner.
My take so far is I will leave my air intake stock, I was looking at the T/A cold air set-up but came to the conclusion that the cold air from the hood intake would be better served cooling the engine (my concerns about water coming through and messing up my clean engine boy so far have been non existent) more so than the cold air would have effected the engine HP.


Reading you post above makes me think the Hellcat cold air box would be the preferred option.
 

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I know a CAI is good for better sound and looks. It is interesting to note that the 2006 concept car had a CAI.


 

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First post.

Ive been searching and cant really find anything on this. I don't understand how a T/A with a cold air type of setup, plus hellcat light setup, plus functional hood scoop isn't worth anything in terms of hp. If that's the case, there's no point in ANYONE buying a CAI for their cars. Not to mention the T/A is a CAI plus more.

Any thoughts on this?

One theory I heard was that these cars are speed density, so a CAI won't make a difference because speed density won't compensate for the extra, and cooler, air like a Mass Air system would. That kinda makes sense. I've had over 20 yrs experience with the fox body mustangs and they were MAF cars.

Air density changes with temperature. My info is speed density systems also rely upon an intake mounted temperature sensor to use in helping to determine the fueling required.


While I can't vouch for all cars every car since my '96 Mustang GT had a "cold" air intake, cold in the sense that after a bit of driving to remove the heat from heat soaking of the air box and intake manifold upstream of the MAF (which also provides intake air temperature) the air temperature was close to ambient.


By close I mean to within 10F degs. or so. Some cars were a bit worse. My Boxster for example. This was due to the the relatively long path the air had to follow to get from the side of the car where the intake vent was located to the MAF and beyond.


The job wasn't made any easier because being mid-engine type car the engine compartment ran warmer then say a car with a front mounted engine.


I have not bothered to check my JCW's intake air temperature mainly because like the Hellcat it is not naturally aspirated but is turbo-charged. That and to check the JCW's intake air temperature I need to connect an OBD2 code reader/data viewer to the car's OBD2 port -- which I have I have just not bothered to connect it yet -- or a data logger to its OBD2 port. I have in fact a data loggere connected but it is not configured to obtain/log intake air temperature. Instead, among other things, I log intake manifold pressure.



With the Hellcat I don't have to have a logger connected to know what the various engine telemetry are. (I do have a logger connected though I just have not bothered to download the data.)


With the Hellcat I can call the individual readings up on the dash or even run Performance Pages and display the telemetry of interest on the LCD. The Hellcat I/C temperature of the Hellcat runs about 10F over ambient. The intake air temperature is higher but is higher but lower than it would be without the inter cooler.


Based on what I have observed over the years if you want a cold air intake leave the stock air intake system in place and figure out a way to bring down the engine compartment temperature. Still I doubt you'll be able to really gain that much in actual performance even if you manage drop the intake air temperature that final 10F degs. or so.
 

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Quote: "I think most folks get to hung up on cooler air in these cai set ups, it's about airflow, not the cooler air making the difference, cooler air still matters"


There's a difference between a 1/4 mile "best time", and a street driven car's drivability.


Not sure about the V6 Challenger engines, but the Hemi's heat soak badly in Summer type weather, just a fact. This will noticablt effect the street drivability of a Hemi powered Challenger.


More air flow won't do much if anything on a car that isn't being raced, which it isn't on the street. Cooler ambient air, and more of it, will assist in getting better throttle response in hot weather for street driving.


My experience was that the 5.7's seem to heat soak more than the 392's do. My '10 R/TC has better hot weather throttle response with the 6.1 bottom air box installed, compared to stock.


My 392 doesn't heat soak nearly as bad as my previous 5.7, but the addition of the HC air box bottom and tube, improved hot weather throttle response on the street.


No numbers to prove this, no dyno runs, just 7+ years of street driving, and feeling the difference that "more ambient air" makes on throttle response during hot weather.
 

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I thought it interesting that the SRT has this huge airscoop, but when ya open the hood, it only blows air on top of the motor, and nowhere near the air intake... Disappointing :(
 

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For ram air to be effective it has to be a straight shot and a high pressure environment for the engine to be forced to take in more air. if the air has to travel and bend it looses it's ram air effectiveness- in the case of the hood scoop on the challenger it's in the middle of the hood, the air is piped forward of the scoop to the corner where the air filter is, the air is making changes in direction and it has to travel, this scrubs off any ability of the air to have a ram effect, along with the air enters into the air box which is not a fully sealed unit so there is no extra pressure to feed the engine. effectively the scoop is for show only and serves no function.

Those of you that have the challenger scoop, go out and do a test, drive your car on a pre planned route, take note of the iat then come home and tape off the scoop and go drive the same route and note the iat. my guess there is no difference in iat reads. your not getting any ram effect to make more power, however you might have a chance to be able to run a few iat degrees cooler, I doubt it but it would be neat to see a test like this done to see if your getting any cooler air.

To get a ram effect you would need a scoop right in front of the throttle body and have a direct shot of air to enter the engine where the scoop can catch air build pressure and force more air into the engine then it would normally be able to do without it. The system has to be completely sealed with no "air leaks" otherwise the pressure built up leaks out before it enters the engine.

take note of the drag cars with scoop, the air is grabbed just right above the carbs and forced into the engine, the air don't have to travel thru piping or have a bunch of bends, the scoop gathers air at high speeds and the air is pressurized within the scoop forcing extra air into the engine plus getting cooler air then whats under the hood.
 

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I thought it interesting that the SRT has this huge airscoop, but when ya open the hood, it only blows air on top of the motor, and nowhere near the air intake... Disappointing :(
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Scooping in increase drag and also internal pressure. I would have scoop to pull out air from under the hood. Reduce drag and temp for also a better cooler intake air

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Also..
Scooping in increase drag and also internal pressure. I would have scoop to pull out air from under the hood. Reduce drag and temp for also a better cooler intake air

Sent from my LG-H932 using Tapatalk
Depends on the size of the scoop, you can still have scoops that don't create any addition drag, the one on the srt 392 are low enough it's not creating any more drag, that scoop allows cooler air into the engine compartment and it exits down below the firewall behind the belly pan. there is low pressure under the car, the air comes in from the scoop or any other air leaks the front has and that air passes over and down the engine out thru the bottom pulling heat away from the engine compartment.

Look at the top speeds of a scat pack and srt 392, I have not looked as of this writing, are the top speeds of the two cars the same? If so then the scoop is doing nothing to frontal drag. A scoop that is much larger will sure cause some drag and effect top speed.

Now get a scoop like I had on my v6 and that sucker is disrupting the air in a bad way, but it did allow more air exchange in the engine compartment to keep things cool, but there was no performance gain from it, any gain was wiped out from the drag, the hood just looked cool and provided room for the supercharger.

You not really going to notice any serious drag til you reach about 100 mph, that's an old rule of thumb from my younger days, just something i heard for many years. Think about it, if your racing a 15 second car that runs 80 mph do you really think it will be a lot slower with a big ol hood scoop, no it's not going to be any worse of.

Now if your car is able to hit 100 plus mph paying attention to what you have on your car makes a difference.

On my challenger when I was naturally aspirated, I taped off the entire front end of my car, I ran a best of 99.xx mph one day at the track, I really wanted to break the 100 mph trap speed. I tapped off both upper and lower grills, tapped off the hood scoop. This was enough on my next pass I ran just over 100.xx mph, I think it was just less than 1 mph in trap speed taping off the entire front end.

later on I found more power where I never tapped off the front end again to break the 100 mph barrier, but this just gives you an example, you really got to be moving, as your speeds get higher above 100 mph the more important all this frontal area really comes into effect.

So between the srt 392 and the scat pack which has the higher top end?, if they are both the same then you know the scoop on the srt 392 is to low and not creating any additional drag because if it was, I think there would be around a 5 mph difference or so on top speed between the two. I'm sure some testing was done for that scoop on the srt 392 to keep it low enough not to cause any issues.
 
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So here's a scat pack that ran 176 mph



So here's a challenger srt 392 hitting 175 mph and also claimed to hit 180 mph later but not on video


I know it's not very scientific but they are two example with two different hoods running at a high rate of speed, at this point the hood scoop does not appear to hinder the srt 392 any over the scat pack with a normal hood.

Any other examples? Be interesting to see.
 

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Good question - and I have the same question about the 5.7L T/A versus other 5.7L Challengers. My car (stock other than a catch can) recently made 351 HP @ the wheels. Is that in line w/ other 5.7L Challengers or a bit higher?
What year is your car? I ask because most '09-'16 5.7 challengers (pre active exhaust models) would dyno consistently around 330rwhp. I've noticed in some of the Mopar Action and Mopar Muscle magazine dyno challenges that results like yours seem to be popping up on the new 5.7 Challengers leading me to believe the '17+ Challengers have a few more ponies with the new exhaust. Wishful thinking perhaps, but I noticed this prior to your post (assuming you have a '17+) and have being questioning this. My '18 "feels" faster than my '13 5.7 did.
 

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Also..
Scooping in increase drag and also internal pressure. I would have scoop to pull out air from under the hood. Reduce drag and temp for also a better cooler intake air

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Thats how NASCAR use them they pull from the cowl since its a low pressure area.




CAI are all about heat soak which on a stationary dyno you are never going to see any gains. They only way I would test one is use your HP guage on your car if you have one in performace pages.

I have the AFE one in my Jeep and after a few miles of steady driving it can get the temps down 15F above ambient and a long 20 miles drive at highway speed it can get down to 10F. I would hazard the first mile after a long heat soak it might be same or even worse than the stock box.
 

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FWIW, speaking of IAT's, here's what I had for readings on yesterday's 250 mile cruise.


99 outside temp reading at 72 mph. IAT reading was 104. Outside temp did hit 100 for a stretch, and IAT reading was 105.


I have the HC air bottom box and headlight tube, with a HC filter on my stock 392 Scat Pack.
 
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