Featuring a variety of options and built to withstand over 2000 horsepower, the RHS® LS Race Block is designed for hardcore racers and street enthusiasts alike. Robby Gordon even uses the block in Dakkar Rally and Baja competition. The block is designed from heavy-duty A357-T6 aluminum, features a 6-head bolt design with a full water jacket around the cylinders, and is Gen III and Gen IV compliant from the LS1 up to the LS9.
Here we answer some of the most frequently asked questions about this revolutionary engine block. What is the benefit of the RHS® LS Race Block?
The RHS® LS Race Block
is the ultimate LS block
for racing and performance, yet remains user friendly by retaining all of the provisions and using the factory hardware from street applications. This includes all external OEM bolt-on equipment such as the oil pan, timing cover and valley plate. As a result, the block is an extremely cost-effective performance upgrade. What is the difference between the standard and tall deck blocks?
The standard deck height is 9.240,″ while the tall block is 9.750.″ The tall deck block provides the opportunity for builders to work with different piston combinations with the block still fitting under the factory cowl with factory heads and intake. How big can you make an LS Race Block?
The largest size is 502c.i.d. The block is engineered for maximum clearance around a 4.600″ stroke crankshaft while still utilizing a 2.100″ rod pin. The side oil galley has been moved outboard and engineered for rod clearance. A raised cam centerline meanwhile (.388”/9.86mm) allows for larger stroke. The LS Race Block
is also designed to utilize stock gears with a chain that is two links longer. A variety of timing set options are available from single to double row chains and gear drives. What valve train upgrades are available with the block?
All blocks come with the cam bearings installed and micro finished. The cam tunnel will accommodate up to 60mm roller bearing cams and includes cast-in lock screw pads. The block utilizes .842″standard lifers but has material available for oversized lifter bores (accepts 1.060″ bushing for keyed lifters). The LS Race Block
also utilizes tie bar design lifters as opposed to the factory plastic tray style. In the standard deck, the maximum pushrod angularity is less than two degrees. Are these blocks available without liners installed?
Yes, the blocks can be special ordered without liners, but RHS®
does not recommend doing so. How does the oiling work?
For priority main oiling, the larger diameter main oil galley was moved outboard for long stroke clearance. The oiling system is dry sump friendly with provisions for external oil pumps or more serious wet sump setups. It includes provisions for piston oil squirters, and utilizes four twin-tube design oil squirters for the priority main oiling. Provisions are cast-in and machined, and only require the final pilot hole to be completed when installing the squirters. The oil filter feed galley “dog bone” has been replaced with proprietary, no restriction threaded plugs. When are oil squirters necessary?
Oil squirters are typically used in applications featuring power adders, but they are good for some circle track racers too. They are beneficial any time the application is going to see high piston temperature. What is the purpose of extra-thick surface material?
The extra thick deck is provide better head gasket retention and add rigidity to the deck surface to prevent distortion in high horsepower and boosted applications. What other features set the RHS® LS Race Block apart from the competitors? RHS®
conducts a CT scan, similar to one performed in the medical field, on each block to ensure maximum precision and consistent wall thickness. What’s more, each block comes with a rear cover and cam thrust plate that are unique to the RHS® block
due to the raised cam. Finally, intake spacer plates are available for the tall deck applications for LS1, LS3 and LS7 heads.