Comments by "Matthew Loutner" (@Matthew_Loutner) on "How Does A Carburetor Work? | Transparent Carburetor at 28,546 fps Slow Mo - Smarter Every Day 259" video.

  1. The throttle restricts the airflow into the engine at low speeds. That slows the engine down because it cannot draw in the full amount of air/fuel mixture. When the engine is throttled down, the cylinder cannot fully fill up. So it uses less air/fuel mixture and the combustion pressure cannot press down on the top of the piston so hard. That slows the rotation down and the engine makes less horsepower. Opening the throttle lets the cylinder fill up to it's full capacity, so you get the maximum amount of air/fuel mixture into the cylinder. The combustion makes more pressure on the top of the piston. Then it rotates faster and makes more horsepower. It is filling with air, but the fuel is mixed in the air and carried in at the same time. The throttle cuts off the airflow mainly -- but it is an air/fuel mixture.
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