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Re: B cam lobes and timing

To: "Allen Blackmon" <orangedawg@hotmail.com>,
Subject: Re: B cam lobes and timing
From: "Tom Phelan" <tomph@mchsi.com>
Date: Tue, 26 Nov 2002 17:50:07 -0500
Hi All,

Just a thought but wouldn't it be more accurate and helpful to Allen to give
a degree reading on the crank when a particular valve should start to open
rather than trying to guess at cam lobe clock positions?? Assuming that the
valve clearance is set correctly you would only have to give one valve
reading in order to determine if one of the cam timing chains has shifted a
tooth. For instance. Set crank at TDC Note valve such and such. Turn crank
in the normal run direction. Valve number "what ever" should start to open
in "x" degrees. Am I in left field here or does this make any sense??

Tom "watching the grass grow in the outfield" P



>
> What's this?  Another timing question from that moron?  Okay, here's the
> latest.  I suspect the shop that put my engine together screwed up.  When
> the engine is at TDC, what are the positions of the cam lobes for #1 with
a
> B cam?  Should the cam gear top screw be at 12?  If so, then my lobes are
> not at 10 and 2 (more like 11 and 2:30).  Or should the cam lobes be
> equidistantly apart from the "noon" position and pay no attention that the
> cam screw is not at noon?
>
> If you've read my prior posts, you are aware of my problems starting this
> car.  As it is now, I can only get it to run when the ignition is set at
> about 35 - 40 degrees BTDC.  Which if my cam gear is off one tooth,
> corresponds to about 20 BTDC.  Also, my car backfires and I see a bit of
> exhaust coming out of carbs, as well as fule coming back out of both
carbs.
> In this condition it does not run as intended.  I've checked timing and it
> is firing 1-3-4-2 counter clockwise as required.  Also have Gary's EI, so
> that is not a problem.
>
> Further, if I turn the crank by hand (w/o plugs) it is very hard at a few
> points, so hard that I need a bit of help to get it to move.
>
> In looking in the cylinders, I can see in #1 a slight mark that would
> correspond to a valve hitting it.  So it looks like the shop set it up
> wrong.
>
> I have moved the cam gear over one tooth.  Turning the engine by hand is
> easier than the way it was set up by the shop.  I have not yet turned the
> engine over by teh starter as I would like List advice on my issues,
> including cam lobe positions.  TIA

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