318 cranks

Forged crank listed as used on all 1967 LA 318 engines. '68 and later all are reputed to use cast crank except for some or all medium/heavy duty truck engine and marine apps. 318 cranks are not supposed to have any rod throws drilled out like cranks intended for 340 engines and are balanced for lighter rods. With all 273, 318, and 340 engines sharing the same bearing sizes and stroke, using the same flywheel and damper mountings, and all forged and cast cranks being neutral balanced except the 72-73 cast crank 340 (because of the heavier rods), after 40 years finding either one in any compatable engine block is possible. With the certainty of forged cranks issued only in 64-67 273s, 67 318s, a smattering of truck 318s, and 68 to mid year 72 340s, and cast cranks being used in over 20 years of 318 production (even discounting Magnum versions), finding a cast crank 318 is far more probable.