"The factory stock pulley is designed to absorb both torsion and bending
lateral vibration from the crankshaft. This helps the crankshaft deal with
high vibration in the 400 Hz range after the #1 piston fires. Overall this
has many benefits on the bottom end. It helps the crank deal with high
continuous loads as well as overall bearing life, not to mention overall
engine life. Also the drive-line will have a more pleasing sound with very
little 400Hz vibe's setting up."
Scott, true the figure was refering to noise but this was the thrust of the discussion...