I would look into the Fidanza stuff as Brandon recommended or Competition Clutch for higher capacity single disc clutches. We have used the Stage 3/4 CC stuff in several customer cars with great results. We haven't really thrown that kind of power at either of these clutches thus far though.
You could also skip the single disc stuff all together and get a QM twin
PM me if you are interested in a price, I think you will be surprised in regards to the pricing on this guy...
Chris