Knife-edge a race crank?

[velocedoc]

Harmonic balancer for a 4 cyl...would the crank shaft pulley from an Alfetta work as they had the outer part separated by a rubber spacer...ie similiar to a harmonic balancer. If not, what could work...or do we just not even contemplate going there?

[AR67202]

would the springs in a standard clutch plate not work as a harmonic balancer aswell? ie, for a road going car with a lightened crank...