Dizzy side hole

J

jhowes

Well-known member
I'm looking over the three dizzy's that I need to rebuild and all have a difference in the dimension of the slot where the upper plate timing lever sticks out. One measures 1" wide by 3/8" high. Another measures 1 and 1/4" by 3/8" high. The third is smaller and measures 3/4" wide by 3/8" high. I think the first one is correct but I thought I had better ask. Thanks Jack
 
I would only guess without seeing a picture of all of them. The last one 3/4" wide possibly an older one. The others will give you more advance timing range. Either way Ford advised to not trim the opening in the body. It was made to limit the angle to 20degrees.
 
Later distributor bodies have "webs" to reinforce where the bale clips attach with rivets.

Earlier not so much.

Joe K
 
the narrower slot was used until the end of 1930. the early levers were narrower than the later levers. The maximum advance was 20 distributor degrees and 40 crankshaft degrees.
 
The distributor body opening for the timing lever should limit the spark advance to 20 degrees. A 20-degree limit was appropriate back when the Model A was and gasoline octane was about 50. However, today we have 87 Octane gasoline, so the engine can run with more than 20 degrees maximum advance.



Some folks time the engine with the spark lever down a few notches because they know from experience, it makes their Model A's run well.


I suggest that you use the distributor body with the widest opening that permits the greatest amount of full advance, and iterate the timing by adding lever-down notches until you find the maximum advance that your engine will tolerate.
 
Thanks to all. I think I will use the 1 and 1/4 one because it is brown and I like the contrast. Jack
 
Bob Bidonde said:
Some folks time the engine with the spark lever down a few notches because they know from experience, it makes their Model A's run well.
Click to expand...

Seems to me that timing the engine with the spark lever down a few notches will REDUCE the amount of possible advance. What am I missing?
 
You must log in or register to reply here.
Back
Top