You can set the cam, if you don't know that magic degree number (110) or check it if you do, by the "Equal lift on overlap" method.
When No.1 cylinder is on the firing stroke and at TDC, No.6 (or No.4 on a four cylinder) is between two cycles. The exhaust and inlet valves are, respectively, closing and opening, overlapping, as the piston goes through TDC. If the cam is correctly set, then at TDC, the two valves should be equally open, at equal heights above the closed position.
Hope that helps,
John
--Previous Message--
: I have reached the point during the GT6
: engine rebuild where I need to set the
: cam timing. I have new TR6 duplex
: pulleys and chain so I have no
: dots/marks/scribe lines to work with.
: Let me describe what I have done and
: please tell me if it is right. This is
: the abridged version.
:
: I found true TDC and set my degree
: wheel to zero. I turned the crank
: forward in the normal direction of
: rotation until I reached 110 degrees,
: the LCA for the S2 cam I have. Then I
: turned the cam by hand until I found
: the max lift on tappet #2 (intake for
: cylinder 1) and fit the timing chain
: and camshaft sprocket. To check this I
: turned the engine in reverse PAST TDC,
: then advanced towards 110 degrees and
: confirmed I still had max lift on
: tappet 2 at that point.
:
: Please let me know if I am doing this
: right. I am used to dealing with
: marked pulleys and it has been almost a
: decade since I degreed a cam.
:
: Thanks,
: Doug L.
:
:
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