Any of you guys have experience with the C4 automatic transmission? My son has a 1972 Mach one that has been rebuilt but has a 2-3 flare up. We can't seem to adjust it out. It happens on normal or manual shift up. The rpm may go up to 5K before dropping into gear.
If it already has a shift kit, the only fix it to take it out and do some drilling on the direct drum. On higher HP cars, you need clutches and Kolene steels also.