Ok well trans has almost 130k original miles. has been put through hell and back. meaning lots off street racing but only one track night with about 4 water box burn out. and car has resently been tuned and is making 286whp 329wtq(mustang dyno). so more like 320's whp and 370's wtq on a dyno jet.
Anyways the issues im having are:
Trans slips from 1st to 2nd with performance shift off. its fine with perf shift on.
And the most recent one since my tune and zzp shift kitt install is that when accelerating from a dead stop(quick take off with less than half throtle) it feels like clutch chatter from a six puck clutch on a manual car or almost like wheel hop. it chatters about 4-5 times then its stops and feels like it grabs and goes. but if i just drive off really slow till it gets going then accel fast its fine.
the 1st to 2nd slipping= before tune and shift kit
the chatter when accel = after tune and shift kit
my guess would be the first issue could the the clutches and the sec issue maybe the torq converter. but i am not to handy with transmissions so i cant say for sure.