I had a Spec II+ clutch and steel flywheel installed last July by a very reputable mechanic that specializes in Mustangs and Lightnings. The clutch was certainly stiffer, and oddly the Hurst shifter as well, but I patiently broke the clutch in with 600 miles of weekend and evening driving around town. The clutch loosened up but the shifter was still taking a bit of effort.
I took it to the track and found the shifter nearly impossible to work into gear. Two other drivers said the same thing. We noticed at that point that the clutch pedal was engaging near the floor, and if you suspend the car and turn it on, the rear wheels still spin with the clutch depressed. Given the symptoms, we figure the clutch wasn't disengaging right and most likely wasn't bled properly (tried 3 times with the manual method). Spec tech support recommended a factory spec bleed (vacuum through the brake fluid reservoir). Nothing's helped. First and reverse, especially, just don't want to go in gear. Note there is no grinding so I think the tranny and syncros are fine so far.
If Spec doesn't come through, which early indications suggest, I'm ready to eat the investment and buy a new clutch, and if necessary, another flywheel. Does anyone have any real world recommendations regarding other aftermarket clutches, like Fidanza, Zoom, Centerforce or others? I'm pretty ticked, as my money saved so far was going into sorely needed suspension components, not labor to replace the clutch again.
Thanks for listening.
John