how do i modified the air box on my 87 cbr 600 f1?

 

To convert mine to ram-air, I used some of the HD rubber tubing from Lowe's or Home Depot, and routed it to the inlets on either side of the headlight from the snorkel tubes. Then inside the airbox, remove the resonater(5 screws, its the twin tubes wrapped in foam connected to the snorkel tubes). Removing the resonaterspeed upmy throttle response and allows your carbs to draw air from more then the last 1.5" of the filter, it also lets you have an air reserve for lowend torque, as opposed to the straight tubes to a tiny corner of the box.(it also gives the bike a little more growl)

The only drawback is in the colder monthsI have to pull the tubes out, since colder air is denser and has more O2, it bogs a little from 40-50 degrees, and a lot from 40 down at speed. Idle and slow speed cruising is unaffected. Since I live on a Highway, that does affect my driving. Around town its fine however.

The hard part was getting it all tuned for the higher speeds(seediechrome's posts on his street fighter), I had to take it to the local shop so they could dial it all in, but its plenty fun now!