Requires high-lift springs. The cam for large 117/124/143″ etc. engines. More torque and power throughout RPM range. The dyno run of a modified 143″ engine showed 173 ft. lbs torque @ 3700 RPM and 155 HP @ 5600 RPM (1600-5600 RPM). Note: Bearings; o-rings and hardware are not included.