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See also: oversquare



over square (not comparable)

  1. (automotive) Of an internal combustion engine design, in which the diameter of the piston is greater than its stroke distance.
    • 2012, Donny Peterson, Donny's Unauthorized Technical Guide to Harley-Davidson, 1936 to Present[1]:
      An over square or short stroke engine occurs when the cylinder bore diameter is greater than its stroke length, giving a bore/stroke ratio greater than 1:1. An over square engine allows for larger valves in the cylinder head because the wider bore creates a broader combustion chamber.