Here is what Centerforce recommends for clutch break-in:
Do Centerforce clutches require a break-in period?
Yes. It is recommended to properly seat in the new pressure plate and disc assembly to assure maximum clutch performance. Centerforce recommends 450-500 miles of stop-and go driving before applying full engine power. If your driving consists mainly of highway type driving, extend the break-in period at least 250 miles. If the break-in period is not properly followed, clutch service life and performance may be severely reduced.