Another air box modification thread ! On a budget ?

Hi folks ,

After reading and researching the airbox on the R53 Mini Cooper s I decided to modify my own .
To do this modification all you need is ;

-67mm hole cutter (available from most DIY outlets )
-68mm plastic down pipe from a roofing gutter . ( you only need 4" )
-sandpaper or sand flappy wheel as close to the 67mm as possible .
-chalk
- 2x 60mm-90mm jubilee clips ( you'll need these if you remove the fancy standard clips on the air box , I didn't have the tool to refit those)
- battery/mains operated dril

First of all I removed the air box from the car . Then using the hole cutter I cut a 67mm hole where the original small hole is carefully keeping it as close to the bottom of the air box as possible . I then ran the flappy sanding wheel round the hole opening it up until my 68mm pipe fitted tightly . I then chalked the end of the 68mm pipe . I refitted the bottom half of the airbox. I inserted the pipe through the hole and turned it until the chalk on the end marked the bulkhead panel to ensure the perfect line up. Now remove the airbox again and carefully cut the hole using the hole cutter on the bulkhead panel. Now do the same as before with the flappy sanding wheel so the pipe fits tightly.

Refit the bottom half of the air box and insert the pipe right through the air box and in to the bulkhead . You should have around 10mm sticking into the airbox , and 10mm sticking through into the bulkhead space. Refit your standard panel filter or a k&n panel filter . ( I fitted the standard as its a budget experiment ) refit the top half of the airbox .

Job done

Road test - instant improvement in whine from the supercharger , and even sounds healthier with the improved induction . This was with a standard filter ! So it can only be improved apon.

Cost ? Very little ! :glare:
Difficulty ? Very straight forward .