Join Date: Dec 2002
Location: back in the Hew-Hess-Hay
Re: pulley groove depths
67 L-35, I dug out some matching deep and shallow small block pulleys to compare the depth. These are old genuine GM, not reproduction. The big block pulleys should be simular in depth.
3770245CC .735" front groove, .710" rear groove, short w/p top pulley, deep groove 67-68
3900434AB .540" front groove, .550" rear groove, short w/p top pulley, shallow groove 67-68
3956668CG .630" front groove, .615" rear groove, long w/p crank pulley, deep groove 69
3956666AG .470" front groove, .450" rear groove, long w/p crank pulley, shallow groove 69
3995647AP .630" single groove, long w/p top pulley, deep groove 70
Like a fool I left the only 3858533 67-68 Z-28 deep crank pulley I have at the shop so I cant measure it tonight. If you need that info I can measure it tomorrow and post that too.
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