RHS Bare Block Engine 4.120" Bore 9.250 Deck Standard Main - 6-Bolt Mains HYSLRG11M61 This revolutionary technology has allowed

This revolutionary technology has allowed Flowmaster to shrink case sizes for improved ground clearance

UL Certified

Up to 2 in OD Tubing

2005-2016 Ford F-550 Super Duty

1999-2007 Chevrolet Silverado 1500

RHS Bare Block Engine 4.120" Bore 9.250 Deck Standard Main - 6-Bolt Mains HYSLRG11M61 This revolutionary technology has allowedThis block has a 9. 240 deck height with a 4. 125 bore and a 5. 87 cylinder sleeve length. Cylinder walls are Siamese cast with press in cast iron sleeves. 12AN feeds for dry sumps. Aircraft quality A357 T6 aluminum. 6 Head Bolt Design. In recent years, LS engine technology has revolutionized the GM performance aftermarket. Gen IV engines have set a new standard for factory horsepower and torque. To meet the growing demand of today's high performance