Did you replace the supercharger belt when you replaced the pulley?
667 - GTP/GS/SS supercharged with stock 3.8" pulley (67 1/4" -1708mm)
658 - GTP/GS/SS supercharged with 3.2 - 3.5" pulley (66 3/8" - 1687mm)
difference in length ( 7/8" - 21mm )
With an old belt, the extra slack + reduced contact on the s/c pulley the belt could easily be slipping on cold startup. Just want to confirm it is not the belt before throwing money at the snout.
(I have a newer oem belt on a 3.5" and it will occationally squeak at startup.)
