GM LS LSR Cam - 277LRRHR13

The GM LS LSR Cam 277LRRHR13 by COMP CAMS is a hydraulic roller camshaft engineered for LS-series engine builds demanding serious performance and reliability. This camshaft is designed for enthusiasts and professional engine builders who require a proven upgrade that maintains factory-style hydraulic roller lifter compatibility while delivering measurably improved valve timing and lift characteristics. The LSR (LS Roller) designation indicates this cam is optimized specifically for GM LS-platform engines, making it an industry-standard choice for street, strip, and crate engine applications.

Built with a 277-degree intake duration and 293-degree exhaust duration on a 113-degree lobe separation angle, this camshaft operates effectively across a 1900–7000 RPM range, balancing low-end torque response with high-rpm capability. The hydraulic roller design features intake valve lift of 0.614 inches and exhaust lift of 0.624 inches, enabling superior cylinder head breathing without requiring solid roller conversion or custom valve train modifications. COMP CAMS' precision manufacturing ensures consistent lobe profiles, zero runout, and predictable performance across production-tolerance engine blocks, while the hydraulic actuation eliminates the need for specialized lifter preload tuning.

This camshaft excels in naturally aspirated LS engines where builders prioritize plug-and-play installation without extensive ancillary modifications. The 277LRRHR13 is fully compatible with factory GM hydraulic roller lifters, solid-roller conversion kits, and modern fuel-injection systems. Installation requires standard LS camshaft change procedures—no custom timing sets or specialized tools beyond basic engine building equipment. Whether upgrading a stock LS3, LS7, or LS9 platform, or establishing the foundation for a high-output stroker build, this cam delivers measurable horsepower and torque gains while maintaining year-round driveability and reliability.