WoW !! that really brought out the views when running a blower. A lot of people are right on this one in my opinion. First i gottoa say that i do run a blown alcohol small blk, with a 1471. I would never run even a 671 without the the second 1/4" key at 180*. Hink pointed out better to run a b/blk snout, for sure that true. Someone else pointed out never run a balancer, run a blower hub, true again. I personally run a 2nd 1/4" keyway and a crank support bearing, which is a must if you plan to run a 3" drive and any boost above 5 or 6lbs. I do run the standard sm/blk snout, but back it up with the bearing support and always run a blower crank hub, never a harmonic balancer, they don't work anyway on a blower motor.

JMO

Zip.