CAI Question

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Bar

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OK, someone with more tech skills, help me out. I am looking at my new CAI and wondering what the hell it really does. It seems to me that I replaced one tube for another and simply replaced the air filter (which is probably 99% of this mod) with one that breathes better. Some CAI tubes go right to the plenum box, some do not.

Do you think it is just the filter and the rest is looks? That's how I see it, but I am curious if I am missing anything. Both the stock and the CAI draw air from the same place (relatively cold wheel well).

Thanks in advance. Just curious if I am missing anything.

Bar
 

SilverBolt

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You are correct. The CAI will flow more air at the filter. The tube is supposed to provide a smoother more direct path for the air to enter the throttle body. Eliminating the rubber boots that come stock smooth out the path. The reality of most CAI's is that they offer little improvement in cooling the air charge. Most are still drawing the air from the factory opening in the fender which becomes the limiting factor on the flow rate. Claimed H/P from a CAI only is nothing but smoke and mirrors. Now a CAI and tune will yield some nice improvements.
 

BlueSVT

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I too agree that they should stop calling all the Raptor intakes CAI's!!! It's still drawing from the same place factory does, just increased substantially. Maybe FAI? Factory Air Intake? haha
 

fshol

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I too agree that they should stop calling all the Raptor intakes CAI's!!! It's still drawing from the same place factory does, just increased substantially. Maybe FAI? Factory Air Intake? haha

Reverse the plastic inserts in the hood, connect the airbox to the hole in the hood and call it a RAI (Ram Air Intake)
 

Raptor62

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I too agree that they should stop calling all the Raptor intakes CAI's!!! It's still drawing from the same place factory does, just increased substantially. Maybe FAI? Factory Air Intake? haha

Most all do use the factory location. They remove the factory box and replace it with their open style box. This allows for more air flow to the filter no matter what temperature may be. If you really need more air flow, remove the drivers headlight.
 

SOCOMech

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I too agree that they should stop calling all the Raptor intakes CAI's!!! It's still drawing from the same place factory does, just increased substantially. Maybe FAI? Factory Air Intake? haha

That's because considering it draws from the inner fender, it is a true CAI.....it's isolated from drawing in air from the engine compartment but gets it from where air is able to move around more and be cooler. If it were to draw air from directly inside the engine compartment, like the AFE for example (it does not seal to the hood), then it would not be considered a CAI. However, the term was developed a long time ago in the performance world due to drawing air from a "cooler" spot than by the engine, so it stuck. "COLD" air it may not be but, it is a bit cooler than engine compartment air.
 

SOCOMech

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19-Kilo

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CAI are a special type of animal. You will see data from people that contradicts each other. Some say it helps and some say you wont see a difference. :argue:

I used to work on tuned race cars :happy160: and have seen the data on the intake temperatures in different conditions. As the vehicle moves air flow in the engine compartment increases and allows for more fresh air. :)
For each 1 degree of air temp increase over ambient air temp you will see a percentage loss in HP.

Hence the comments about how winter air at 32 deg F will be better than hot summer air for power because it is cold and dense.

Cliff notes: a CAI will work good at slower speeds by providing consistent cold air to the engine.

An intake that gets its air from under the hood ("short ram") will take in hotter air at slower speeds (i.e. stopped) because the engine heat raises the intake temp of the air under the hood. This increased intake air temperature will cause the engine to pull timing and adjust fuel air ratios to compensate for the hotter air... causing less power to be produced. :( Once a vehicle is moving you will not see under hood temps that much over ambient because of all the fresh air coming in.

A CAI will take in the ambient air temp all the time no matter the speed so you will not notice a loss in power at decreased air flow (or vehicle speed)


On my old race car (Subaru WRX STI) :flamingdevil: I saw a noticable hp loss for every degree over 85 deg F (the max effective temp for my intercooler heat exchange). So when my under hood temps reached 120 deg at a stop light (only 60 sec stopped), I was almost 50hp down from when I was moving and getting ambient air temps of 85. The air intake temp took over 2 min to cool back down once the vehicle started moving again. I saw under hood temps around 10 deg higher than ambient when moving at moderate to high speed. So a CAI will help when moving, but not much (hence all the data you see about CAI being a myth) :birgits_tiredcoffee

Hope this helps provide some clarification on what a CAI will help with and when.
 
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