Fidanza alum flywheel with steel inserts, Southbend SS with organic disc, 600ft lb rating.

Over the weekend I attended Powercruise USA at Brainerd International Raceway. I was running into some bad clutch slip on the straights after a good 10 minutes on the track.

If I was running a little harder and shifting coming in and out of corners, I would slip on the straights once boost built and I got higher in the rpms.

If I limited my shifting and just staying in one gear through the corners, I would not slip on the straights.

I suspect this is a heat issue. I've always read good reviews for Southbend, and have never had slip on the street. This clutch is rated at 600ft lbs, I'm at 515whp/509ft lbs. I've had a few peeps online state that the Fidanza alum flywheel has caused problems for them in the past with slipping, and to go steel for road racing. This car was built for road course trackdays, but the way it was going this weekend I wouldn't get but a couple laps before losing the clutch at a faster pace. Even when running harder in the corners, it was still not at a trackday/race pace. Any other thoughts on this?