LSX Bowtie Blocks Deliver the seemingly impossible combination of professional racing level strength and entry-level affordability, the LSX Block is the next revolution in high-performance engine-building. This durable iron-block casting is based primarily on GM's production LS7 block, but designed with more material in key areas-including a thicker deck and bores-to support displacements of 454 cubic inches or more, and unique six-bolts-per-cylinder head-clamping capability that enables forced-induction and nitrous combinations of greater than 2000 horsepower. Because the LSX Bowtie block is based on production LS blocks, all of the LS-Series Gen IV cylinder heads, crankshafts, oil pans, camshafts, and accessories bolt right up to it. There is also a tall-deck version for building even larger engines. GM Performance Parts delivers the LSX Bowtie Block semi-finished, allowing you to finish it to your needs. Whether you're building a "tame" 500-horse street engine for your hot rod or a 1700 horsepower turbo engine for an Outlaw drag racer, the LSX Bowtie Block is the foundation for an unbeatable combination-at an unbeatable price!