Might sound like a stupid question but our trucks stock intake get air from inside the fender so how is that not the same as a CAI?

 

Yeah it is kind of weird, but supposedly CAI's get cooler air than the stock setup with their little heat shields, along with the pathway from the oversized filter to the throttle body being a lot less restrictive.

 

ah ok. CauseI have a CAI on my Stang and it made sense to me but the setup on the truck confused me. I thought about doing a DIY one but its not round so I wasn't sure how to pull it off

 

The stock Dodge 2nd Gen factory air intake is designed to get hot air from the engine compartment when the truck is not moving. This slighly helps the engine idle, and slightly shortens warmup from a dead cold engine.

When the truck is moving, the factory air intake gets 'cold air' from dual sources....behind the passenger side headlight and also from the opening near the antenna mount.

In Kenne Bell testing, they claim removing the entire air box and feeding the throttle body of a 1998 Magnum 5.9 V8 with a large hose of outside air with no filter gives a rear wheel horsepower gain of approximately 8.

See

http://www.kennebell.net/techinfo/do...-test-data.pdf

in my own tests I have found that in front of the air filter (upstream) the stock factory airbox adds about 4 inches of water restriction, compared to the pressure of the air around us which is about 401 inches of water (also 14.7 psi and 29.9 inches of mercury)

The factory airbox is also designed to avoid
sucking in bugs,
road dirt or
large water droplets,
and it is about as high in the engine compartment as possible, which is good for crossing streams of water.

It is not designed to be an all-out drag racing item.

 

8hp is a pretty big jump for just changing the intake