another idea ... a decepticon ("moped bill") is putting together a wickedly fast puch free spirit. he put his 70cc kit on it and is hitting about 50mph. and he's going to put on an airscoop.
he's just going to turn the airbox around on the puch, since the puch airfilter is funnel shaped and paints back. by turning it over to the front and forward, it should force air into the moped at the faster speeds and make a difference. the air filter would still be there and everything. it sounds like a good idea to me.