The worst sludged engine I ever tore down was using Pennzoil.
But that was in the 70s
If you don't make mistakes. your not doing anything.
69 ss rs full custom camaro 98 ISCA grandchampion
69 ss rs bb camaro wifes driver
66 Elcamino 350/all dz parts,ac,windows,loaded,my driver
69 ss chevelle bb conv.fresh frame off
26 T sedan street rod