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Performance engine preparation. Cam timing. Check accuracy of TDC mark. Use a positive stop to determine. Rotate crankshaft each direction. Difference is TDC. Performance engine preparation. Timing a cam using the intake centerline. Install degree wheel on damper.
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Performance engine preparation • Cam timing Check accuracy of TDC mark • Use a positive stop to determine • Rotate crankshaft each direction • Difference is TDC
Performance engine preparation Timing a cam using the intake centerline • Install degree wheel on damper • Dial indicator on #1 lifter (retainer for OHC) • Zero indicator at valve wide open • Back engine up ¼ turn, then clockwise to .050” • short of zero. Make note of number on wheel
Performance engine preparation Timing a cam using the intake centerline • Continue clockwise to .050” past zero & make • note of this reading • Intake centerline is halfway between the 2 readings
Performance engine preparation Timing a cam using the intake centerline • Cam timing can be advanced with offset bushing • or key
Performance engine preparation Piston-to-valve clearance • Assemble entire valve train for cyl #1, using light • springs on the valves • Adjust valves to proper lash • Check clearance before & after TDC during overlap • Should be a minimum of .100” • Proper geometry