Whats the best aluminum cylindar heads?

The car weights 3000lbs but I have some fiberglass parts to put on, so I should shave it down another 100 to 150lbs. The car has a full roll cage front to back and full weld in fram connectors, Caltracks with a Dana 60 with 410 gears, Dynamic 8" convertor and 727 with tranny break. Where can I find these stage VI heads, who makes them?