Hot street cam for 88 to 95 inch. Twin Cam 88''s have shown 80+ horsepower on rear wheel; more with 95 incher. Smooth idle; broad torque band. Runs best with low restriction exhaust. Works well with both carb and injection. Stock springs OK. 2200-5600 RPM. These cams are used to convert a 99-06 Twin Cam from the stock ''silent chain drive''; which is equipped with spring adjusters; to the ''roller chain drive'' with hydraulic adjusters that work on engine oil pressure. This roller chain and hydraulic chain adjusting system; which is much better than the early system; is used in all 06-17 Dyna and 07-17 Softail and 07-16 Touring models. Note: Cams are for use with splined (00-up style) driven gear. For 1999 Twin Cams splined 503575 driven gear must be purchased separately. Note: See our catalog for additional required parts.