GM Vortec engine

Vortec is a trademarked name for a line of big block engines for General Motors trucks. The name first appeared in a 1984 advertisement for the 1985 model year 4.3 L V6 that used "vortex technology" to create a vortex inside the combustion chamber, creating a better air/fuel atomization. Now it is used on a wide range of engines. Modern Vortec engines are named for their approximate displacement in cubic centimetres.

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