the 383 cranks are ex less you have a hi rent crank so it will use a 400 damper and fly wheel or auto wheel. balancing is balancing if all your parts are for the mass .it is fun when you make one internal that was set UP FOR EX balancing it cost $$ in heavy metal on the ex you need the damper and the fly wheel you would use seeing how this is weight for the counter weight if you do not then the front and back of the crank get drill and reamed for heavy metal