GM LS Thumpr Cam - 283THR

The COMP CAMS GM LS Thumpr Cam 283THR is a purpose-built hydraulic roller camshaft engineered for GM LS-series engines seeking aggressive street and mild performance driving. This camshaft is designed for enthusiasts who want noticeable power gains and audible valve train character without requiring extensive engine modifications or solid roller conversions. The Thumpr series delivers the distinctive mechanical aggression that LS builders and engine rebuilders have trusted for years, making it an ideal choice for street cruisers, weekend drivers, and performance restorations.

This hydraulic roller design features 283 degrees of intake duration and 303 degrees of exhaust duration with a 109-degree lobe separation angle, creating the distinctive thumping exhaust note the series is known for. Intake valve lift reaches 0.563 inches while exhaust lift measures 0.546 inches, optimizing flow characteristics across a broad RPM band from 2300 to 6600. The hydraulic roller design eliminates the need for constant valve lash adjustment while providing durability and reliability that rivals mechanical designs, and the conservative lobe profile keeps the camshaft compatible with factory-style valvetrains and stock cylinder head castings.

Builders and engine shops rely on this specification for LS engine builds targeting street performance without sacrifice of daily drivability. The 283THR pairs seamlessly with factory fuel injection systems, stock intake manifolds, and OEM-style lifters, minimizing compatibility concerns during installation. Users should verify their specific LS platform variant before purchase, as this camshaft is engineered exclusively for GM LS-series applications and requires proper lifter selection and installation per COMP CAMS specifications.