M3_Power 636 Report post Posted April 27, 2013 This is the full airbox (not the upgrade kit airbox with the cone filter) - the volume of this airbox is much larger than the standard Cooper S R56 airbox and gives noticeable gain over the standard Cooper S when used (better blow off valve noise also). As seen in the photo below on the right hand side (left hand side standard Cooper S airbox) $150 (these are over $300 to buy brand new) Quote Share this post Link to post Share on other sites