.575" valve lift. IOG = gear drive cams with Inner & Outer drive Gears. Complete kit with installation hardware; bearings and gasket. For stock 103" engines with stock 9.7:1CR up to 10.5:1CR. Works well with un-ported heads and great for S&S CNC ported heads. Best power in the higher RPM range. 3000-6000 RPM. Easy Start Cams make starting easier by reducing the build-up of cranking pressure in the cylinders during starting. This is done by lifting the exhaust valve slightly of its seat; with a spring loaded compression release lobe inside the camshaft. After starting the compression release lobe is retracted by centrifugal force. The only difference is during starting since you will now be able to electric start your Big Inch engine effortless; without the use of big batteries and/or starter motors. A stock starter and battery is enough. When the engine is running the camshafts function as regular cams; without any loss in power; torque or anything else. Note: Not compatible with S&S 79cc heads. Note: Required installation kits for Easy Start Cams are included in this complete (IOG) kit. They are separately available as replacement from S&S for this kit as 503566. Note: No Easy Start Cam grind is bolt-in for these 99-06 Twin Cam models. All will / may require clearancing and require high lift valve springs. Note: Not compatible with kickstart models. Note: Camshafts made before Jan. 2010 will require adjustable pushrods. Note: Below 900 RPM you may hear a cl