I don't think a Chevy cam will fit your Pontiac engine. The lobe #'s are the same,but can't switch between two different type blocks.
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‘63 LeMans- ‘69 400 w/ original transaxle. 2.69 gears.
‘55 Catalina
‘62 Mercury Meteor-all original, bought new by my grandfather
71' GTO -original 400/4-speed/3.23 posi
13.95 @ 102.1 on street tires @ 4055lbs.-now my sons ride