273 crank in 318 bennifts??

For the record forged cranks are HEAVIER than cast, that is why the cast crank 340's needed an external counterweight. The 340 also had the heaviest rotating mass of any small block, that's why cast crank 318's were neutral balanced. The weight difference was mostly in the pistons. 340 pistons were the largest diameter, and had the tallest compression height of any small block pistons, and also the heaviest.