Block Specifications: Designed from heavy-duty A357-T6 aluminum material; 4.125”-4.165” siamese cast bore walls w/ press-in spun cast iron liner; Available in standard (9.240”) & tall (9.750”) deck heights w/ beefy .750” deck thickness; Both standard deck (5.67”/5.87”- same as LS7) & tall deck (5.94”/6.38”) cylinder liner lengths available; “Long arm friendly” – Accommodations for up to 4.6” stroke w/ standard rod pin diameters (2.100”) & oversized 60mm camshaft; Main cap surface area maximized at mating surface & large fillets from cap to cross bolts for added strength; Designed for clearance – side oil galley moved outboard & engineered rod clearance come standard; Significantly increased windage passage area under bores & around caps over LS7/LSX engines; 6 head bolt design w/ full water jacket around the cylinders (based on LS7 design); Bay-to-bay breathing improved w/ increased side window area versus LSX & LS7; Extra-large windows in valley for access to inboard “6th” head bolt; Extra-long liners for standard (5.87”) & tall (6.38”) decks

Genuine Edelbrock. Part number 54903U.

Ships from US warehouse.

WARNING: California Proposition 65 — this product can expose you to chemicals known to the State of California to cause cancer or reproductive harm.

Note: Not CARB approved — not for sale or use on pollution-controlled vehicles in California.