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Piston-Valve Clearance

How to Degree a Cam

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Hi, i just watched the How to Degree a Cam, and i have some questions.

1) Is there any way to check piston-valve clearance other that taking the engine apart?

2) When Using High lift camshafts on a variable cam timing gears for example VTC (from Kseries). How do i find where is the maximum advance i can go when tuning the VTC map before piston to valve contact?

You will need to test assemble several times while checking piston to valve clearance. Certainly easier to use stock parts.

I recently assembled a K20 with VTC and high compression pistons, I unlocked the phaser mechanism per the manual with compressed air, then kept the mechanism at full advance using an L-shaped piece of aluminum I filed to fit into the visible hole in the front (essentially a stop). I added clay to each valve pocket, and moved the VTEC pins to force the high cam. Did two revolutions at maximum advance, then removed the stop, and repeated with the cam fully retarded.

Fortunately I had plenty of clearance for the valves (but the Mahle PowerPac pistons did not have sufficient spark plug clearance so I had to mill the top of the pistons).

Thank you sir!