I think we lost Tyler. He'll be careful before he opens a topic like this again. Where is CarbKing when you need him? I can venture a guess: he is sitting home reading this and laughing so hard the beer is running out his nose. He's laughing because we are shooting at a mouse with a 10 gauge, all us amateurs. But I think we can put away all those big Italian words. No matter what Red says, the vacuum comes from the pistons going up and down and the valves opening and closing. The counter intuitive part of this is that if the pistons were strictly a vacuum-creating machine, the faster they went the greater the vacuum would be, and the faster the wipers would go. This would be true if you could find a way to increase RPMs without opening the throttle. With the throttle closed, the vacuum has only two ways out, one way is the little hose to the wipers, the other is the even smaller idle jet, so the wipers get plenty of suction. When the throttle is open, then the great big main throat vents all that vacuum out to the atmosphere. At that time a big volume of air rushes through the throat and you can start talking about Bernoulli and Venturi, these are the guys that decide how the much fuel gets sucked into the motor. But with the throat (throttle) open the vacuum will rather vent through the throat than that little hose to the wipers.
How long can we keep this topic open before we all go to sleep? Tyler, are you there? Do you say "Uncle?"
