GM Performance 19434604 Small Block Chevrolet Crate Engine - 400 HP (ASA LM Spec.Engine)Crate Engine SBC 350 400 HP (ASA LM Spec. Engine) Crate Engine Circle Track 400 404 HP Not IMCA Legal Small Block Chevy HIGH REVVING PERFORMANCE AND DURABILITY Chevrolet Performances CT400 racing crate engine now features Fast Burn cylinder heads with LS style beehive valve springs that enable greater high rpm performance and durability. They allow the engine to rev higher to make the most of every cubic inch of air drawn through it. The result is a