Stroke: 3 31/32" 4 1/4" 4 3/8" 4 1/2" 4 5/8" 4 3/4" 5" Bore: 3 7/16" 3 7/16" +.010 3 7/16" +.020 3 7/16" +.030 3 7/16" +.040 3 7/16" +.050 3 7/16" +.060 3 7/16" +.070 3 7/16" +.080 3 1/2" 3 1/2" +.010 3 1/2" +.020 3 1/2" +.030 3 1/2" +.040 3 5/8" 3 5/8" +.010 3 5/8" +.020 3 5/8" +.030 3 5/8" +.040 3.780" 4" 4 1/4" Displacement: cubic inches Displacement: cubic centimetres (Last updated 25-10-98)

Select the stroke and bore of your engine and then press the calculate button As a guideline: K P S E Stock 74ci stroke: 3 31/32" * * *   Stock 80ci stroke: 4 1/4" * * * * Stock 74ci bore: 3 7/16" * * *   Stock 80ci bore: 3 1/2" * * * * Big Bore 3 5/8" * * * * Sputhe Big Bore 3.780"       * S&S Big Bore 4"       * Harmon Big Bore 4 1/4"     *   Keck Big Bore 4 1/4"       * K=Knuckle, P=Pan etc...