When I need serious calipers, I found the Toyota 4 x 2 inch puck calipers for $70.00 to work exceptionally well in competition, The Mazda finned aluminum calipers are getting hard to find but very nice as well, but smaller pucks .
[URL]https://www.rockauto.com/en/ca....4l+l4,1277782,brake+&+wheel+hub,caliper,1704[/URL]
Fab or modify mount brkts .
Good luck