Y-Block Engines

 317 cubic inch

  • Cast nodular iron crankshaft supported by five bearing journals at 2.62inch
  • Rod journals measured 2.249 inches
  • 8.0:1 compression ratio and 205hp at 4200 RPM
  • An improved Holley carb, high lifter cam, dual diaphram distributor and freer flowing exhaust


341 cubic inch

  • Last only for 1955
  • Increased bore to 3.94 inches
  • Compression ratio of 8.5:1 with 225hp at 4400RPM and 332ft.lb of torque

368 cubic inch

  • Introduced in 1956
  • Increased bore and stroke to 4.00X3.66
  • 285hp @ 4600 RPM with 402ft.lb. of toque
  • Compression ratio is 9.0:1
  • Larger exhaust valves at 1.64 inches, bigger fuel pump and dual diaphram distributor
  • Black painted valve covers and air cleaner
  • Following production year had slightly revised enhancements including 10.1:1 compression, Carter four barrel carb and a spin on/off oil filter