Timing the Cam- dist

[Terry, NJ]

I get how to time the cam to the crank, but how do you time the distributor drive gear to the cam? Eng is on TDC now. Also, I was thinking of making a timing pointer to bolt on the cam gear cover and scoring the pulley. Anyone know how large is one degree?
Thanks in advance,. Terry

[Bruce Lancaster]

No need. Your rotor is phased to the cam, cam can be freely rotated to the necessary position when you put it back together and time it. Clearest instructions for that are in Marco's site or in your owner's manual.
http://www.abarnyard.com/workshop/timing.htm
Marking a pulley the easy way:
Measure diameter. Steal a protractor and compass from an eighth grader who is in Geometry 101.
Draw a circle the size of pulley rim on a piece of cardboard, use protractor to draw an arc of 40 degrees or so on that circle. Mark that off in whatever divisions you want.
Cut out circle, hold outer piece of cardboard or a section of it to the pulley rim and mark, starting with TDC found during timing procedure.

[Napa Skip]

Bruce offers a simple and direct answer to the "how large is one degree" question.

From an engineer's standpoint (never underestimate the ability of a registered engineer to complicate an otherwise simple matter), one degree would be 1/360th of the crankshaft pulley circumference, which gives us the opportunity - inasmuch as the circumference is related to the diameter by the ratio of approximately 3.1415926 - to introduce pi.

Soooo...for a 5-1/8" diameter crankshaft pulley (the diameter of the two pulleys I just measured), the width of 1 degree at the crankshaft pulley circumference would be about 5.125" x 3.1415926... (this could go on forever) / 360 = 0.04472406". [Inquiring minds want to know...]

Having said that, I've always found the conventional method of timing my Model A's to work very effectively, without the aid of timing marks, strobe lights, etc. But that's just a personal opinion...

[Terry, NJ]

Thanks Bruce and Skip. Dammit I should have had that one on my fingertips. I feel so DUMBBB ! I/360th of Dia. Yiiiiiiiii ! And So it doesn't matter where the cam gear is cause you reset it by changing the distributor cam? Gotcha. I am having a hard time getting used to a distributor cam that moves! Never had one of those before! I wanted the pointer for a timing light.
Terry

[Bruce Lancaster]

I like the cardboard disc way because calculating the size of a degree at X inches usually results in something like that 0.04472406 in Skip's example! Try laying out 40 of THOSE neatly! I kind of like 5 degree divisions...not too busy, and pretty easy to subdivide by eyeball as needed.
But again...with stock distributor, no real need. All necessary to set the base timing is already part of the car, and from there the correct timing is whatever makes the engine feel happy...
I think degreed pulley would be most useful with a centrifugal distributor so you can get an idea of what it is actually doing.

[Tom Wesenberg]

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I'm with Skip and like Henry's original simple way of timing.

If you still want to use a timing light, then I'd make a single reference mark on the crank pulley and put the degrees on the stationary plate next to the pulley.

[Patrick L.]

Thanks Bruce and Skip. Dammit I should have had that one on my fingertips. I feel so DUMBBB ! I/360th of Dia. Yiiiiiiiii ! And So it doesn't matter where the cam gear is cause you reset it by changing the distributor cam? Gotcha. I am having a hard time getting used to a distributor cam that moves! Never had one of those before! I wanted the pointer for a timing light.
Terry
end quote

It really does matter where the cam gear is. Then you turn the points cam. Even if you want to use a timing light the cam gear should be about where it needs to be as well as the points cam.

[Pete]

Or you can be lazy and use timing tape.

http://www.autozone.com/autozone/acc...ier=139829_0_0_