All those holes on the intake edge of the smoothbores were put there to make them look fancy. Only three serve a purpose. On the 33, the choke air intake is one, the air intake for the main jet system is one and the pilot jet system is one... just like every other VM series carb. The reason for the choke air inlet is to supply air when the slide is closed. The same with the main and pilot circuits. One of the two is pressed in brass and the other is a small screw-in jet. I can't recall which goes to which but if you are curious, get a can of carb cleaner. Open the slide and spray into each of the holes. On the dummy holes, you will get it back in your face so watch out. On the MAIN JET air jet, you will see carb cleaner dribble out the main jet. On the PILOT jet air jet, you will get it spraying up through the small hole behind the needle jet in the bottom of the venturi. This is also a good way to ensure that these passageways are clear. If you the pilot jet test with no jets in, put your finger over the air screw hole (on the side) and the pilot jet well. Carb cleaner should squirt through in a nice mist.