#1 engine. 39-40 merc. 99 stamped block. it is out to 296 c.i.. the center main let loose an broke crank in two. bored to 3 3/8. relived, adj. tappets, ss valves, unknown cam. webber alum. f. wheel. crab dizzy. i guess the crank. must be 4 3/8 to get to 296 c,i. it has sat for a few...