340 crank questions

You can use the lighter crank but if you are using the stock 340 rods and stock 340 weight pistons, you will have to add weight to the 318 crank and that will be costly.

That will all change if you use lighter pistons and/or lighter rods. We have a 273 crank in a 340 and with KB hyper pistons and SCAT rods, considerable weight was taken off of the 273 crank for balance.

What pistons and rods are you planning? It is not hard to take those numbers and compute the bobweight of the new combination and compare it to the standard 318 bobweight.