They open so they can fire the cylinder when the pistion reaches TDC / Top Dead Center.
The speed of the air as it rushes in allows for the air to continue rushing in for a little while after bdc.
Dead center prods was created in 2003.
The top dead center is when the piston has reached its peak and can go no farther up, it has reached its summit. The bottom dead center is when the piston is at its lowest point.
TDC is 0 degrees TDC, not 10 degrees BTDC which is before top dead center. ATDC is after top dead center. Both of these in relation to piston height are "below top dead center".
top dead center is what it stands for. top dead center
The speed of the air as it rushes in allows for the air to continue rushing in for a little while after bdc.
Top dead center on an engine is defined as when the piston is farthest from the crankshaft. Bottom dead center is when the piston is closest to the crankshaft on the engine.
The distance from Top Dead Center to Bottom Dead Center of piston movement.
The list below is from freedictionary.com:center something on someone or somethingto base something on someone or something. Let us center the discussion on Walter. Our whole meeting was centered on the conservation question. center around someone or something to make someone or something the central point in something; to be based on someone or something. Your salary increases center around your ability to succeed at your job. The success of the picnic centers around the weather next week.center of attention the focus of people's attention; the thing or person who monopolizes people's attention. She had a way of making herself the center of attention wherever she went. center on someone or something to focus on someone or something in particular. Let us center on the basic problem and try to solve it. I want to center on Liz and her contributions to the firm. dead center at the exact center of something. The arrow hit the target dead center.When you put the flowers on the table, put them dead center.off center not exactly in the center or middle. The arrow hit the target a little off center. The picture hanging over the chair is a little off center. on dead center 1. Lit. at the exact center of something. The arrow hit the target on dead center. When you put the flowers on the table, put them on dead center.2. Fig. exactly correct. Mary is quite observant. Her analysis is on dead center. My estimate wasn't on dead center, but it was very close to the final cost.----
Measure the distance a piston travels from bottom dead center to top dead center.
The distance from Top Dead Center to Bottom Dead Center of piston movement.
With a 2 stroke or 2 cycle engine if the ignition timing is set too close to top dead center it can start to run backwards.