See more about this engine here: http://blogs.hotrod.com/433ci-big-block-chevy-by-performance-crankshaft-at-amsoil-engine-masters-challenge-2014-145453.html
This is an Engine Masters entry from Performance Crankshaft has a 4.325 bore by 3.680 stroke big-block Chevy for 433 cubic inches. It made 643 horsepower and 582 lb-ft of torque during the dyno competition at the 2014 Amsoil Engine Masters Challenge presented by HOT ROD. Engine Masters is an annual shootout of engine builders in competition for huge cash prizes. For 2014, the Challenge is for two-valve V8s above 400ci, running on 101-octane fuel, and making optimal power from 3,000-6,500 rpm. The competition is held at the University of Northwestern Ohio.