set crank and cam #1 TDC firing position (#6 cam lobes are at "point of rock" ie ex closing/inlet opening)
set up chain and gears, rotate through to where it reaches max cam lift, should be 110 ATDC (ie use inlet opening 31 before, add 180 stroke TDC to BDC, add 71 ABDC = 242, divided by 2 due to cam half speed of crank = 141, -31 initial BTDC =110 after TDC measured at crank)
Then continue rotating crank through the cycle until again the indicator reads .013, it's on the opening ramp now and the valve is just ready to open and it has taken up the "checking" clearance.
This should be 31BTDC on the crank.
Keep rotating the crank to the point of where the valve is almost closed, back at the .013.
This should be 71 ABDC
a few more points-
-hopefully you have better than stock pushrods, Ted can supply.
-you can make an "extended" tappet using a couple old tappets open end-to-end and a short length of tube to connect them, gives you something to measure off.
-Also it's hard to measure the exact point of max cam lift. Once you think you have it established, pick up a point around 5 thou before max cam lift, measure crank degrees, rotate a little more just past max lift until the clearance is again .005 less than max, measure indicated crank degrees and confirm center is between the two.
-This is just the way I do it, you can also start off by simply setting it up initially at the opening points ie 31 BTDC on the crank and .013 off the base circle on the opening ramp.
Hope this helps answer your question, there's more if necessary...
Glen
--Previous Message--
: Ok... I'm dense. Please spoon feed me.
:
: What do you mean the checking clearance
: is 0.013" at the cam? I don't
: think you are saying 0.013" of
: lift at 31 degrees. Don't you need a
: degree and a lift figure to check
: position?
:
: Doug L.
:
:
: --Previous Message--
: The checking clearance is .013 at the
: cam.
: Glen
:
: --Previous Message--
: Thanks Glen,
:
: However, I don't have any additional
: specs on the S2 cam. I know the LCA is
: listed as 110 degrees and the intake is
: said to open at 31 and close at 71.
: However, no "checking"
: dimensions were given. (No specs like
: "at .050" lift the crank
: should be at X degrees"). All I
: can do at this point is set the cam for
: 110 degrees, then back the crank WAY
: backwards and then forward again to see
: if I can detect the very beginning of
: lift and the point of closure. I am
: just not confident I'll be able to find
: those two points since we are talking
: about a transition from
: "zero" to
: "something" on the indicator.
: Hopefully Ted S. will have some
: additional specs I can use to set the
: angle.
:
: Oh... I am only turning the engine
: "forward" during these
: measurements to eliminate backlash and
: slack errors from the chain and
: sprockets.
:
: Doug L.
:
:
: --Previous Message--
: I set them on the lobe center, and then
: check opening and closing points at the
: checking clearance, just to be sure.
: Be sure to take the slack out of the
: chain before you take a reading.
: Glen
:
:
:
:
:
:
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