A regular Grade 5 bolt will work OK, with a drop of blue LocTite and about 50-55 ft/lbs. of torque once the balancer bottoms out against the timing gerar. The bolt is really an afterthought- - -as long as the press fit is right, millions of stovebolts have run untold millions of miles with no center bolt at all. If you've got one of the 216 balancers with the hand crank lugs on it, a little machining needs to be done to create a step for the heavy washer under the center bolt to bear against. I have installed a lot of pistons on small block V-8 connecting rods by heating the small end of the rod until the wrist pin is a slip fit- - - -it's a lot less stressful on the piston than trying to press the pins into the rods. The same thing happens when a balancer hub is heated a little.
Jerry
