[Supras] New clutch slipping, shifting problem?

[Walker, Brian (Rich. Dist)]

I put about 700 miles on my new clutch (kevlar) and FW (AL.) before a
time trial this weekend. During one lap it started slipping very
noticably in 3rd so I let off, applied throttle again it was again
slipping, much more than the stock unit ever had. Earlier in this lap I
had made a poor shift to 2nd where I mistakenly slipped it a fair
amount, could this be the reason it was slipping in 3rd and 4th? I know
I'm not making the 460 ft-lb. the clutch is rated for (I'd guess I'm in
the 320-340 hp range with similar torque)
I was under the impression that the clutch will not slip once engaged
unless it's TQ rating is exceeded, will poor engagement between shifts
(ie: excessive heat) cause it to slip prior to this?

Thanks,
Brian W