Small block 340 engine for sale and some questions...

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• 1972 - The 340 four-barrel dropped to 240 horsepower:
  • Compression dropped to 8.5:1; the compression height of the piston via wrist pin location changed by 0.10"
  • The crankshaft was switched from forged to cast somewhere in the production cycle, believed to be in early April 1972, with engine 39118000 (thanks, Karl Thomas)
  • 340/360 were moved to "J" casting heads with 1.88" intake valves; exhaust valves remained the same
  • Paint went from orange to corporate blue
• 1973 - The cast crank had a different number than the 1972 counterpart, because it was shot-peened for greater strength.