I am considering a CAI for my MC. I understand why the CAI may provide a modest gain in performance. What I don't understand is from a design perspective, the CAI seems much less complicated than the stock filter/intake system on the MC. If that is the case, why didn't the designers simply provide the CAI intake in the first place? What is the benefit of the stock intake with the plastic box and the extra ductwork, etc.?

 

1) Noise. EU regulations on auto noise are very restrictive, and most of the humans find high-pitched intake noise annoying.

2) Cost. A paper filter traps more fine dust, extends engine life, and it is lower total cost for the manufacturer to simply replace a throwaway filter than to clean a permanent filter, when you consider the cost of labor.

 

Ditto the above, plus no manufacturer wants to rely on the avg. customer's ability to realize/remember/follow thru on cleaning/oiling a permanent filter. Finally, at least with respect to the current Cooper, there is little to nothing to be gained in power from CAI - some people like the additional sound (or noise depending on your perspective) & some don't

 

Is the danger of getting water through an aftermarket intake higher than the stock? Or really no difference?

 

Not much difference, really... Although, the stock airbox will tend to provide a bit more protection, but not much. The pickup point for both is about the same place.

I'm running the aFe, and I really like it - sounds a bit more tame and refined than the Promini intake it replaced.

 

i know about the CAI and short-ram, but there is something else, it was like a "hot air intake", why would anyone want that?
and is it really worth it to get the intake, because the stock air box is getting the air from the grill, like cold air.

 

There are other threads on this topic, so feel free to search re: the CAI and HAI issue. I'm not convinced that a wall created with aluminum (and excellent conductor of heat) significantly reduces the performance of an intake. Both CAIs and HAIs offer greater surface area of filter and less restricted air flow. The placement of most aftermarket intakes is exactly where the air box was, so you get fresh air through the stock tube.

I've thought of adding a piece of tubing onto the end of the stock air tube to direct even more air to my K&N Typhoon. Anyone ever try this?

 

I believe some had played around with the idea of placing a container of some sort around their intake (coffee can perhaps?) and running a duct to the coffee can making sure the cold air goes directly to the intake. Don't know if they tried it or not.

 

I would like to try! But the last post in this thread was from 7+ years ago...