Gen III, IV, Small-Block Crate Engines Part Number Description Liters CID Block Material HP Torque Bore Stroke 19165628 (discontinued) LS327/327 5.3 327 CI 327 347 3.780 3.622 17801267 (discontinued) LS1 5.7 346 AL 350 365 3.898 3.622 19165484 (discontinued) LS2 6.0 364 AL 400 400 4.000 3.622 19172842 (discontinued) LS364/440 6.0 364 AL 440 404 4.000 3.622 19434650 LS364/450 6.0 364 CI 450 441 4.000 3.622 19416591 (discontinued) L96 6.0 364 CI 360 380 4.000 3.622 19435100 LS376/480 6.2 376 AL 495 473 4.065 3.622 19435102 LS376/515 6.2 376 AL 533 477 4.065 3.622 19435104 LS376/525 6.2 376 AL 525 486 4.065 3.622 19435098 LS3 6.2 376 AL 430 425 4.065 3.622 19370850 (discontinued) LSA 6.2 376 AL 556 551 4.065 3.622 19260165 (discontinued) LS9 6.2 376 AL 638 604 4.065 3.622 19434598* CT525 6.2 376 AL 533 477 4.065 3.622 19329246 (discontinued) LS7 7.0 427 AL 505 470 4.125 4.000 19421004 (discontinued) LS427/570 7.0 427 AL 570 540 4.125 4.000 19432776 LSX376 B-8 6.2 376 CI 476 475 4.060 3.622 19417356 LSX376 B-15 6.2 376 CI 473 444 4.060 3.622 19417357 LSX454 7.4 454 CI 627 586 4.185 4.125 19331506 (discontinued) LSX454R 7.4 454 CI 776 649 4.185 4.125 *For circle-track racing only. Not for street use. 53 CHEVROLETPERFORMANCE.COM LS-SERIES CRATE ENGINES • 6.0L – Used primarily in 3⁄4-ton and 1-ton trucks, the 6.0L (364 cu in) uses an iron block (LY6) or aluminum block (L76) and aluminum heads, with provisions for Active Fuel Management; some are equipped with variable valve timing. • 6.2L – Commonly referred to by its L92, L9H or L94 engine codes, the 6.2L (376 cu in) engine uses an aluminum block and heads and incorporates advanced technology, including variable valve timing. The L92 is used primarily as a high-performance engine for the Cadillac Escalade and GMC Yukon Denali. MORE ABOUT THE VORTEC 5.3L With more than 10 years in service in millions of Chevy and GMC trucks, vans and SUVs, the Vortec 5.3L engine is poised to become the classic 350 Small-Block of the LS engine family. With millions in service, it is readily available and affordable on the used-engine market. Most feature iron cylinder blocks, but some have an aluminum engine block that is about 80 pounds lighter. Adapting a 5.3L to a hot rod project is easier with Chevrolet Performance’s 5.3L controller kit, P/N 19369180. It covers 2007–2009 applications (non-cam-phased) with the following engine codes: • LC9 (2007–2009) • LH8 (2008–2009) • LMG (2007–2009) • LY5 (2007–2009) • LMF (2008–2009) LSX CRATE ENGINES Chevrolet Performance LSX series of crate engines is based on the LSX Bowtie Block and uses a number of production-based and LSX high-performance parts to deliver ultimate-performance engines that were never offered in production vehicles. They include: • LSX376-B8 – An economical crate engine that uses the LSX block, LS3 rotating parts and the LS3 cylinder heads. It is offered without an oil pan or induction system, so that it can be tailored for the project vehicle. • LSX376-B15 – Designed to accommodate additional power adders or boost up to 15 PSI. Includes forged pistons, forged crank and 6-bolt LSX-LS3 cylinder heads. • LSX454 – The displacement of the classic Big-Block, with an all-forged rotating assembly and LSX-LS7 six-bolt cylinder heads. It is rated at 627 hp with a carburetor and 580 with an LS7 fuel injection system. • LSX454R – A high-compression (13.1:1) version of the LSX454 designed for drag racing, featuring a mechanical roller cam, high rise intake and more. It is capable of more than 750 horsepower. NOTE: Discontinued in 2018 (N/A) NON-PRODUCTION CYLINDER BLOCKS C5R: Developed for the factory-backed Corvette racing program, the C5R cylinder block has been manufactured in comparatively small quantities since 2000. They are manufactured with a unique aluminum alloy for greater strength and undergo a variety of specialized machining and inspection processes, including “hipping” to increase strength and X-raying that ensures against unacceptable porosity. A Siamese bore design with 4.117-inch finished bores enables 7.0L (427 cu in) displacements. The C5R uses billet steel main caps with premium 4340 fasteners. Racing-quality head studs are also included. All LS series heads will work with the C5R block, but maximum performance depends on maximum airflow. LSX Bowtie Block (standard and tall-deck): Introduced in 2007, the LSX Bowtie Block is a durable and affordable cast-iron casting that was designed to support extreme high-performance combinations, including provisions for six-bolts-per-cylinder head fastening. It has a Siamese bore design with 3.880-inch bores that must be finished to 3.898 inches, with a 4.200-inch recommended maximum bore. Maximum stroke can reach 4.25 inches, but rotating assembly interference on the cylinder must be taken into account for strokes greater than 4.125 inches. Heavy metal is required for crankshaft balancing of larger-stroke combinations. Standard versions feature decks 0.020-inch taller than LS production blocks, with the tall-deck version manufactured with a 9.720-inch semi-finished deck height. The oiling system is a true priority-main system and all LS Small-Block heads work with the engine. Higher-airflow heads, such as LS7, LSX-DR, LSX-CT and C5R, are recommended. CRANKSHAFTS Generally, LS crankshafts are similar in design, with identical 2.100-inch rod and 2.560-inch main journal sizes and a common rear main seal. All LS engines use iron crankshafts except the LS7, LS9, LSA and LSX454; they use forged steel cranks (4.00-inch stroke on the LS7; 3.62-inch stroke on the LS9 and LSA; and 4.125-inch on the LSX454). The crankshaft sensing function of the distributorless ignition system depends on reading the toothed reluctor wheel on the crankshaft. Early LS engines mostly used 24-tooth (also known as 24Xe) wheels and upgraded a few years ago to 58-tooth (also known as 58X) wheels. When building an LS engine, it is imperative the correct reluctor wheel is used with the compatible crankshaft position sensor and ignition controller. The crankshafts are mostly interchangeable, but the snouts on LS7 and LS9 crankshafts are approximately 1 inch longer to accommodate their two-stage oil pumps, which work with the engines’ dry-sump oiling systems. The same goes for certain Corvette applications of the LS3, which was available with a dry-sump system as well. These forged crankshafts can be used on wet-sump engines by using a few specific components and/or modifications. The LS/LT Engine Family Tree continued on next page
