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Now that the degree wheel and pointer are set up to read exactly TDCNow that the degree wheel and pointer are set up to read exactly TDC, a lifter is installed on the No. 1 intake lobe, and a dial indicator or a special checking tool is set up to record the tappet rise. The object is to read from the degree wheel exactly how many degrees past TDC peak intake lift occurs. Begin by rotating the crank and zeroing the indicator at peak lift. Since the exact point of peak lift is difficult to distinguish, a checking height is used when reading the degree wheel. I use both 0.025 and 0.050 inch, recording the degree wheel readings at these points before and after the indicator goes over the nose of the lobe. The installed centerline is determined by averaging the degree wheel reading at a given checking height before and after peak lift. When making the checks, always rotate through the checking positions in the normal direction of engine rotation.