[DevilsReject97]

Originally Posted by newmoon

Are you sure. The below article clearly mentions: Smaller-diameter supercharger pulley

https://media.chevrolet.com/media/us...amaro-zl1.html

I stand corrected. Thank you for that correction. Now that I see it I do remember it.. I've been drunk since then!

GM did the pulley upgrade...with their own Drag Pak. Stands to show my original statement of why GM didn't do it as valid all by itself.