The lopey idle you want. The low-RPM torque you need. The COMP Cams Thumpr NSR camshaft brings the iconic Thumpr idle lope to the GEN III/IV HEMI platform — without sacrificing the street-friendly low-end pull or requiring a valve spring upgrade. What Makes the Thumpr NSR Different? Getting that racecar idle sound used to mean giving up low-RPM torque — a trade-off that made most aggressive cams impractical for street-driven HEMIs. COMP Cams engineers solved this with optimized intake and exhaust lobe profiles that deliver the unmistakable Thumpr lope while preserving the torque characteristics your HEMI was built for. Key Features No Valve Spring Upgrade Required — Drop-in friendly for GEN III/IV HEMI engines Thumpr Idle Lope — The signature lopey idle sound without the street-use penalties Big Power Gains — Optimized lobe profiles deliver real performance across the RPM range Preserves Low-RPM Torque — Engineered specifically for street-driven HEMI applications Specs: 214/233 Duration — Thumpr NSR grind Installation Notes ECU tune strongly recommended DOD/MDS deletion recommended Phaser limiter required for VVT-equipped GEN IV HEMI engines Fitment 2009–2022 Dodge/Chrysler GEN III/IV HEMI — 5.7L & 6.4L Part #: 201-700-17