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RHS® LS Aluminum Race Block

Racing New Product Photo1
Airflow technology leader introduces a high performance GM LS engine block for all-out racing applications.

GM LS engines have truly set a new standard for V8 performance and durability. However, there are limitations for the aftermarket shopper when it comes to finding a high performance replacement for the factory block. Aware of this dilemma, the research and development team at RHS® went to work designing and testing several different versions of GM LS engine blocks until they found the optimal solution for performance engine builders and racing enthusiasts.

The LS Race Block is designed for added clearance and mass customization. Available in both standard (9.240”) and tall (9.750”) deck heights with an extra-thick deck surface (.750”), this RHS® block features a raised cam centerline and priority main oiling via an oil galley that is shifted outboard to allow rod clearance for a much larger stroke (4.600”) while also minimizing windage in the crankcase. Using computer-aided design, the cylinder walls are Siamese cast with press-in spun cast iron liners. Cylinder liners are available in both standard deck (5.67”/5.87” – same as the LS7) and tall deck (5.94”/6.38”) lengths. Also featured is a 6-bolt head design with a full water jacket around each cylinder (based on the LS7 design).

For quality control assurance, RHS® performs a CT scan on each block (similar to a medical CAT scan) to maintain maximum casting precision and consistency. Combine all of these features with a superior finish quality, thanks to the RHS® patented Clean Cast Technology™, ultra-precise computer aided design and extra surface material to allow custom machining, and you’ve got a GM block that sets a new benchmark for LS horsepower, torque and durability.

Quick Summary:
Product: RHS® LS Race Block
Part Number: #54900 (9.750” Tall Deck, 4.165” Bore); #54901 (9.750” Tall Deck, 4.125” Bore); #54902 (9.240” Std. Deck, 4.165” Bore); #54903 (9.240” Std. Deck; 4.125” Bore)

Features & Benefits:
• Designed from heavy-duty A357-T6 aluminum material
• Available in standard (9.240”) & tall (9.750”) deck heights with beefy .750” deck thickness
• Accommodates up to 4.6” stroke with standard rod pins (2.100”) & oversized 60mm camshaft
• Raised cam centerline (.388”/9.86mm) to allow larger stroke; 2 extra links in the timing chain
• 4.125”-4.165” Siamese cast bore walls with press-in spun cast iron liner
• Priority main oiling, galley moved outboard for longer stroke clearance & minimal windage
• Dry sump friendly with big front & rear AN-12 side feeds
• GM Gen III/Gen IV compliant with race mounts for Gen I, Gen II, Gen III & Gen IV engines

For more information about the RHS® LS Race Block or any other RHS® product, call us at 1-877-776-4323