A
Cold Air Intake or CAI brings colder & denser air into the engine, thus increasing horsepower and torque. Usually the increase is anywhere between 8 – 15 WHP (Wheel Horse Power) depending on how the engine responds to bolt on modifications. You also need to consider the general design of the engine and its position within the engine bay, as the CAI becomes more or less effective depending on how far it can get away from the "heat" of the engine, plus the direct nature of the pipe going directly into the engine (vs. a pipe that twists and turns its way through the engine bay like you see in late model Honda Civics).
Some engines have a very restrictive air intake, so the CAI really does make a notable improvement.
Most CAI are sold by aftermarket companies, and usually go from $100 - $200. Go on e-bay and you can see some “homemade” CAI’s that are about $80 and offer comparable performance but lack the visual WOW that a Injen or AEM CAI might have.
Also, you will have a much more noticeable engine “roar” with a CAI, as you are usually replacing several plastic parts designed to “quiet” engine sounds with a straight metal pipe.
However, there are several downsides to a CAI. The first being the risk of
Hydrolock. Since CAI’s are near the front and bottom of the engine there is the risk that the air filter (or the opening where air is being sucked in for the engine) might become submerged in water via a puddle. This then results in water being sucked inside the engine and into the combustion chamber. Since water does not “compress”, this can cause the engine rods to snap, or the engine block itself to crack.
From personal experience I can tell you that this is a REAL possibility. I equipped my car with an aftermarket CAI for over a year, enjoyed the performance it brought, but was shocked when I drove through a medium sized puddle and had my car suddenly die on me. I had snapped a rod, and I can tell you it was no fun paying the bill to have my car fixed.
I now use a Short Ram Intake, which is the same as a CAI except it does not extend outside of the engine bay, which protects your engine from the risk of Hydrolock. It does not perform as well as a CAI as the air it sucks in is not as cold (as the filter never extends outside of the engine bay), so it only brings a 8 WHP gain.
Now, as far as this relates to the Saturn Sky… is this a Factory option being offered by Saturn, or a local dealer? If the factory is offering this as an option then it would have to be covered under warranty, just as a Turbo in the Redline version would be covered under warranty. You would probably be protected if you Hydrolocked your car.
Also, I can see Saturn charging $400 + for a CAI for several reasons. The first being that a $200 CAI from an aftermarket company would void the warranty… a $400 one right from GM would not. If we are talking about an option you can add onto the MSRP of the vehicle and then finance, then $400 sounds like a good deal. Pont number 2 is that the NA (Naturally Aspirated or Non-Turboed) Sky owners might want a performance boost so that they are not totally left in the dust by the Redline Turboed Sky’s… and a CAI might just be the type of mod most Sky owners would be willing to do if it was covered under the warranty. Remember that a CAI is a VERY EASY mod, especially compared with other NA mods (Exhaust, Headers, Cams, and so on. The only easier mod would be a racing chip), so it could be a relatively cheap way of boosting performance closer to the redline level.