I just took a thorough look at my S's air box components. It consists of a single chamber air box with a paper element drop in filter. There is a cold air feed from the back of the air box which is ducted (via a rubber grommet) into the fresh air vent located behind the bonnet and in front of the windshield. There is a second cold air feed via a plastic chamber, which begins directly behind the front upper grill and above the radiator, then raps around the main rubber intake pipe and into the bottom of the air box. This plastic chamber consists of three smaller, dead end chambers (two on the side of the pipe and one long skinny one of the bottom). I've seen these dead end chambers on other cars with similar intake systems. I'm guessing they are used as a form of tuning to create turbulence along the intake path. The airbox itself is relatively small. The top of it can be separated from the bottom via two torx screws (or 5/8 inch socket if I'm remembering correctly). The left side of the top piece possess a plastic hanger setup for the + battery post. The bottom of the box is the complicated part. It is not only the bottom of the air box, but also the base for a wiring harness casing which is to the right of the air box. Removing the entire bottom of the air box would be somewhat difficult and would take some custom work.
All the parts and pieces I just mentioned are pretty basic. No sensors or mechanical parts are anywhere to be seen.
The only sensors I could find were in the main rubber intake pipe, which draws air from the top of the air box and directs it into the supercharger's intake manifold.

So, here is my somewhat :smile: educated conclusion on the factory intake system.
Mini did their homework on this system. It is relatively simple, draws cold air from not one but two places, and is in a pretty good location under the hood. After running my car for 1 hr or so I popped the hood to notice the bottom of the airbox was warm (still pretty cool seeing how its damn close to the exhaust manifold), the top of the box was cool, and the main rubber intake pipe was relatively cool.
I do think this can be improved in two ways.
1.Having a filter with less restriction and more surface space.
2.Forcing more cold air (not under the hood air) to the less restrictive filter.

The current cold air intake systems on the aftermarket are not really cold air setups. They are simply using what Mini has given them (bottom of air box and cold air runners) and designing a new upper section of the air box, which in most cases uses the bottom part of the hood as the top of the box. The true cold air setups that I'm accustom to are similar to the AEM design that place the filter itself in a place outside the engine compartment, rather than using factory runners to bring air to their own filter. It seems almost impossible to make an AEM type of setup (hoping someone proves me wrong) with the tight space under the hood.
Advantages of current so called "cold air setups":
1. Less restrictive filters with more surface area
2. Cool intake sound with the absence of the top section of the factory air box.

Now, after all this am I ordering one of these so-called "cold air" intake systems?
HELL YES....
I'm willing to spend a reasonable amount of money to get a louder intake sound and a real world 2-4 hp gain (not some altered misleading dyno gain). I will probably decide on the company that blows the least amount of hot air up my *** (no pun intended).

Hope this helps some of you.
Please post some of your experiences with the system you have installed.

IU

 

Thanks for the info. I am interested in a cold air intake as well. I saw somewhere on a post someone took a generic system, for like $40 and it seemed to work as well as those touted by the big name suppliers. Any thoughts?

 

One way that a true cold air type intake could be made is if the intercooler is moved to in front of the radiator. If there is enough room to put the intercooler there then intake tubing could be run from the scoop to make a ram air type set up. Moving the intercooler to a front mount position also has two added benifits. You can have a larger intercooler then with the top mount design and the intercooler will no longer be contaminated by waste heat from the motor.

 

agreed, but no room for the intercooler in the front. It would take a ton of custom work to get this done.

IU

 

As someone who (still) hasn't had time to really get at their MINI, thanks for the info... A question that me and my brother in law had is, where the heck is the supercharger? Anyone?

Rocketboy_X

 

In front of the motor beneath the intercooler.

 

"This plastic chamber consists of three smaller, dead end chambers (two on the side of the pipe and one long skinny one of the bottom). I've seen these dead end chambers on other cars with similar intake systems."

These chambers ar "Helmholtz Resonators" They are used to tune the sound of the air intake system and do not have an effect on performance. First used by Ford in 1973.

 

>>"This plastic chamber consists of three smaller, dead end chambers (two on the side of the pipe and one long skinny one of the bottom). I've seen these dead end chambers on other cars with similar intake systems."
>>
>>These chambers ar "Helmholtz Resonators" They are used to tune the sound of the air intake system and do not have an effect on performance. First used by Ford in 1973.
>>

I disagree. helmholtz resonators do improve dips in the power curve caused by airwave resonance. I wrote a paragraph on it for the Miata about 9-10 years ago.

http://members.aol.com/solomiata/airflowmtr.html

Dyno proven to add 4 rwhp at 3500 rpm in the Miata.

Randy

 

I just ordered a BMP intake. It should be here this weekend. I will schedule some dyno time either saturday or monday to do a before and after test. A new thread will be started when I post the results.

IU