Anyone now what would cause the clutch to slip in 3rd/4th and 5th at about 2500rpm to 3000 rpm when the throttle is nailed. The rest of the time it is fine. I have done the pull away test with handbrake on and it stalls the car. In first and second it is OK even on launch type starts.
It is an uprated excedy organic kit and only done about 3k. It did suffer judder at first but has settled down, with the occasional judder at low revs.

Any advice would help thanks.

 

If the clutch is on its way out, it will slip easier in higher gears.

Where did you buy it from?

 

I bought from GGR. It doesn't slip after about 3k revs.