The foam pad on the original one is a form of soundproofing. Its just an extra expensense they dont bother with on pattern parts.
--------------------- 1989 e34 525 with Dinan chips... traded in at 170,000 miles for 1994 e32 740i with Dinan badge, ...traded in at 190,000 miles for black 2007 e92 335i
my standard volvo aftermarket paper filter also has no foam...i guess it depends on the manufacturer.. re performance you'll probably not notice any difference...
--------------------- James Clay Race Proven Performance www.bimmerworld.com www.bimmerworldracing.com