Can anyone post a link or explain how the air / fuel mix on a MFI CVH works? If I remove the air feed pipe work from the top of the air box. I can see a large circular metal "flap" which is sprung loaded to seal the opening. This to me seems back to front as the air wants to flow out of the air box via this opening through the pipe work I have just disconnected and on to the throttle housing. And the action of the spring is stopping this from happening.

I woiuld of thought the spring would keep the "flap" in the open position and as more air is sucked into the inlet manifold ( and air pressure increases) this would pull against the spring thus allowing the MFI to know to start injecting more fuel to match the increased rate of air flow.

(God I hope that made sense)