.510" valve lift. Set includes two chain driven camshafts. A cam drive installation kit; that includes a gear cover gasket; cam bearings and retaining ring can be ordered separately as S&S 503593. Cams can be run with stock hydraulic lifters. Hot street cams for 88 to 95 inches. 80+ rear wheel HP possible with well tuned 88 incher; more with a 95/96 incher. Smooth idle; broad torque (2200–5600 RPM) 9.0 to 9.5 CR. OK with stock springs. Note: Owners of 1999 Twin Cams must separately purchase the splined 00-06 style driven gear (503575 Andrews). 00-06 models can re-use stock 34 tooth driven gear. Note: When using 99-06 chain drive cams for higher lift applications it is recommended to upgrade to gear drive or to convert to the 06-up hydraulic chain tensioners.