More Fontana Trivia: The aluminum blocks save about 50 lbs over a cast iron Cleveland (or Windsor). They were a composite design, using both 9.2" (Cleveland) and 9.5" (Windsor) deck heights, with a Windsor-type front cover, water pump and fuel pump, and a Cleveland crank, cam, oil pump and oil pan. They could be had with either a 4.060" bore or a 4.125" bore from Fontana. The popular 410" class WOO racers used a 4.125" bore, a 3.83" forged steel crank, Carillo rods (Carillo bought Arias a few years ago), a single Holley carb & put out around 900 bhp @9000 rpm all day long on methanol.
The actual block design was done by Nick Arias for drag racing in the lower size classes, then Don Madden and Joe Fontana bought it from Arias (Don passed away not too long afterwards) and made changes over the years. The engines were also popular (in So-Cal anyway) in street Mustangs. There is one in Norway in a street Pantera, not built by Hall! When the design was sold to Shelby Enterprises in Las Vegas, they dropped the 9.2" deck height option. It may still available from them as the 3rd iteration of Arias' successful early '70s design.