Racing Head Service (RHS) 54901U - LS Block, Tall 9.75" Deck, Ready To Hone To 4.120"

-Tall Deck Height (9.760) -Needs Final Finish Hone Before Assembly -6.38" Cylinder Sleeve Length -4.120" Bore 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 -Raised cam centerline (.388”/9.86mm) to allow larger stroke; 2 extra links in the timing chain – Timing sets available from COMP® -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 VALVE TRAIN CAPABILITIES -Provisions for Gen III & Gen IV cam & knock sensors & valley covers -Cam tunnel will accommodate stock through oversized 60mm roller bearing cams (includes cast-in lock screw pads) -.842” lifters standard with material available for oversized lifter access (accepts 1.060” bushing for keyed lifters) -In the standard deck, maximum pushrod angularity = Less than 2 degrees -Includes Ampco 45 cam thrust plate and aluminum rear cover -Lifter bosses designed to clear tie bar lifter SUPERIOR OILING -Priority main oiling, galley moved outboard for long stroke clearance -Oil filter feed galley GM “dog bone” replaced with proprietary no restriction threaded plugs -Dry sump friendly with provisions for more serious dry sump setups; includes big front & rear AN-12 side feeds -Includes provision for piston oil squirters, cast-in & machined ADDITIONAL FEATURES -Rolled threads on all threaded holes for added strength -Gen III/Gen IV compliant with race mounts for Gen I, Gen II, Gen III & Gen IV engines -ARP main stud kit standard with enough material in castings to accommodate up to a ½” fastener -Chilled main bearing bulkheads for added strength -Optimized billet main caps & improved windage