| Did you notice if the sintered clutch pack had a dished plain plate in it? Most "racing" packs don't and if this is what it was sold as then chances are it'll be missing one to. the dished plate helps with the take up and prevents the graunching.
You can get them seperately for about a fiver. Replace one of the plain plates with it.
Also, did you build the clutch up to suit a slipper? it's different to the road setup up. Friction plate in first, not two plains. | 
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