440 blower manifold BDS or Hampton ???

It is a crank hub - no balancer. The hub is double keyed and I had a guy broach another keyway in the crank. The advice is to double key. I know others say they did not and have no problems. With a hub you gotta figure out how you're going to mark for timing. An SFI rated balancer is the other option assuming the register is the correct size for blower pulleys. You still have to decide on double keying or not.