Our Mustang has an original shaker put on it. But looking at it we were curious as to what would keep the water from getting into your air filter when you were driving if it should start raining. Beings as it is a scoop and it hooks directly to the air cleaner box....what keeps the water out?

 

Nothing keeps the water out. But it doesn't go directly to the air filter, either. You have the flapper valve on the top, that's only open when you are stomping on the gas, and even then the water would have to get through the flapper an make a sharp turn to get to the filter. It's never been a problem.

 

We understand that the flapper valve opens by vacuum. Another question. Our actuator to the flapper valve is broken. The rod that hooks to the flapper is gone. We'll replace this. Does anybody know how this actuator actually works?

 

The spring action actually pulls the flapper open. When the engine starts, manifold vacuum pulls the flapper shut. When you stomp on the gas, manifold vacuum drops, opens the flapper, and allows cold air to come into the engine through the scoop. When you back off, vacuum builds up, and closes the flapper again.

 

why not take advantage of the cold air all the time?

-Gun

 

Because they were intended to be cars, not summer toys, and in 12°F weather (or even 35°F), you wanted to run off the warmer air in the heat riser to avoid having the fuel/air mixture too lean.

 

That makes sense....I live in Ca I forgot it gets colder than 35 some places.