13 The new Lunati camshaft specs are .510 inches of lift on both the intake and exhaust when using the factory 1.625 rocker arms. With a 105-degree valve centerline, the total duration @ .050 was 235 degrees for the intake and 239 degrees for the exhaust. These cams came with a ground-in additional 4 degrees of advance. Notice the specialty tool designed to install both Twin Cam bumpsticks evenly and at the same time. The original inner chain was reused once the camshafts’ timing marks were aligned.