With our big-block Chevy at 0.050 inch on the opening side of the lobe from max lift we recorded 62 degrees after top dead center (ATDC) and then 151 degrees ATDC at 0.050 inch from max lift on the closing side. Adding these two numbers together and dividing by two will give you the intake centerline. In our case: 62 + 151 = 213 / 2 = 106.5 degrees ATDC. The Comp Cams timing card supplied with our cam calls for an intake centerline of 106 ATDC, so we're within 11/42 degree of dead on. This told us that despite the numbers being off slightly at 0.015, the cam is installed correctly. You back the engine up to 0.100 inch on the dial indicator before taking the reading at 0.050 on the opening side of the lobe because traveling past the data point and then turning the engine clockwise to approach the 0.050-inch data point removes any slack that may be present in the timing chain that resulted from turning the engine backward. This is why you don't turn the engine counterclockwise to 0.050, but rather go past it and then turn clockwise up to the first checking point. It's a small point, but accuracy is our goal. TOOL LIST DESCRIPTION PN SOURCE PRICE Cam handle POW101035 Powerhouse $26.95 Dial indicator, 0-1-inch POW151100 Powerhouse 29.95 Dial indicator ext., 1-inch POW151111 Powerhouse 5.00 Magnetic base POW151125 Powerhouse 29.00 Degree wheel, 9-inch POW101500 Powerhouse 16.00 Degree wheel, 16-inch POW101600 Powerhouse 179.95 Cam-checker tool, GM/Ford POW101400 Powerhouse 65.00 Crank nut, SBC POW101050 Powerhouse 15.00 Crank nut, BBV POW101055 Powerhouse 15.00 Pro crank socket, SBC POW103050 Powerhouse 26.25 Pro crank socket, BBC POW103055 Powerhouse 26.25 Piston stop, heads off POW101335 Powerhouse 9.95 Piston stop, heads on POW101330 Powerhouse 9.95 Deck bridge POW101310 Powerhouse 19.00 Deck bridge, magnetic POW101315 Powerhouse 51.95 This is the Comp Cams timing card that comes with every camshaft. Note that Comp only gives valve opening and closing numbers at a 0.015-inch checking height rather than at 0.050.This is the Comp Cams timing card that comes with every camshaft. Note that Comp only give SOURCES COMP Cams Powerhouse Products 3402 Democrat Rd. Memphis TN 38118 800-872-7223 901-795-7600 www.powerhouseproducts.com Powerbuilt Tools/Alltrade Long Beach CA alltradetools.com « | 1 | 2 | 3 | 4 | View Full Article Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!