[Dan00Hawk]

This thread
MINI COOPER :: North American Motoring - Webb Motorsports Airbox Modification How-to
details how to access the partition for venting more outside air to an aftermarket CAI/HAI kit through the cowl. It says it "won't work for a stock airbox".

With that in mind, I studied the design a little more. As there is already a small hole in the stock lower airbox that connects via a grommet to a hole in the lower section of the partition, I figured out that I could add a series of honeycomb style holes in the lower stock airbox and match it up to honeycomb holes in the lower section of the partition, and then seal off the whole thing with some foam insulation to keep out the hot engine bay air.

I chose to do a series of small honeycomb holes for structural integrity purposes (and I didn't want to go buy a 2" hole attachment for my drill ).

The foam isn't quite thick enough to seal completely on one side, so once it was all together, I doubled it up and stuffed some more around it. But these pics give the basic idea of what I did.

The supercharger whine is more apparent now at WOT , but it's hard to tell if I really added any "power". At best, I probably picked up 2 hp and added some more fresh ambient air. At worst, I wasted an hour working on my car, which is always fun anyways. And it's way cheaper than buying aftermarket parts...

My apologies if this has been done by someone already, but I didn't see anything about modding the stock airbox...