RHS LS Aluminum Race Block (Ready to Hone) 9.250" Standard Deck - 4.120" Bore

Standard Deck Height (9.250)
Needs Final Finish Hone Before Assembly
5.87" Cylinder Sleeve Length
4.120" Bore

Engineers at RHS¨ have designed a high performance aluminumÊengine block for GM LS applications to meet the needs of race and street performance engine builders alike. To go beyond the limitations of other existing LS blocks, the new RHS¨ LS Race Block is available in both standard deck and tall deck height configurations. Additionally, this innovativeÊaluminumÊblock features a raised cam centerline and outboard priority main oiling to allow rod clearance for a 4.600Ó stroke and to minimize windage in the crankcase. And for quality control assurance, RHS¨ conducts a CT scan (similar to a medical CAT scan) on each block to ensure maximum casting precision and consistency. When you combine unmatched finishing quality with added clearance for increased stroke applications, precision computeraided design and extra surface material to allow custom machining, you get the new benchmark for LS horsepower, torque and durability.

BLOCK SPECIFICATIONS

Designed from heavy-duty A357-T6 aluminum material

4.125Ó-4.165Ó siamese cast bore walls w/ press-in spun cast iron liner

Available in standard (9.240Ó) & tall (9.750Ó) deck heights w/ beefy .750Ó deck thickness

Both standard deck (5.67Ó/5.87Ó- same as LS7) & tall deck (5.94Ó/6.38Ó) cylinder liner lengths available

ÒLong arm friendlyÓ Ð Accommodations for up to 4.6Ó stroke w/ standard rod pin diameters (2.100Ó) & oversized 60mm camshaft

Raised cam centerline (.388Ó/9.86mm) to allow larger stroke; 2 extra links in the timing chain Ð 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 Ð 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 Ò6thÓ head bolt

Extra long liners for standard (5.87Ó) & tall (6.38Ó) 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)

.842Ó lifters standard with material available for oversized lifter access (accepts 1.060Ó 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 Òdog boneÓ 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 _Ó fastener

Chilled main bearing bulkheads for added strength

Optimized billet main caps & improved windage