Ignition timing Ignition timing In a spark ignition internal combustion engine, Ignition timing refers to the timing, relative to the current piston position and crankshaft angle, of the release of a spark in the combustion chamber near the end of the compression stroke. The need for advancing (or retarding) the timing of the spark is because fuel does not completely burn the instant the spark fires, the combustion gases take a period of time to expand and the angular or rotational speed of the engine can lengthen or shorten the time frame in which the burning and expansion should occur. In a
Archaic–Early Basketmaker Era Archaic–Early Basketmaker Era The Archaic–Early Basketmaker Era (7000 - 1500 BCE) was an Archaic cultural period of ancestors to the Ancient Pueblo People. They were distinguished from other Archaic people of the Southwest by their basketry which was used to gather and store food. They became reliant on wild seeds, grasses, nuts and fruit for food and changed their movement patterns and lifestyle by maximizing the edible wild food and small game within a geographical region. Manos and metates began to be used to process seeds and nuts. With the extinction of megafauna, hunters adapted their tools, using spears with