273 302 318 340 build

Let me understand something.... so you are going with the '70 crank? I assumed you were going with the '83 crank. The later rods should be the heavier ones and should be balanced with with the '83 crank. So why not go with the '83 crank in the '70 block? It should drop right in. Crank register should be the same and all else.....

Did you want to go with the forged '70 crank for a particular reason? Balancing the later rods with the earlier crank (that was originally balanced for the early lighter rods) would require adding weight to the crank and so the price he quotes is not all that surprising. The cheapest route is to go with the later cast crank and rods.

The pins will all interchange, but yes, your issue with the smaller rods is that the bushings in those rods need locks in the pistons as he said.

BTW, I am pulling for the Seantors......