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Old 09-21-2020, 03:58 PM   #21
Bob-A
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Cool Re: B Distributor Initial Timing

I'm not much of a "guru" when it comes to anything Model-A or B. Especially concerning timing degrees or what ever. But, when I rebuilt a "B" distributor to run on my "B" block (with a "B " timing cover) replacing an "A" distributor. I could never find anywhere any instructions on Timing a B distributor!?! Eventually I found on the ..'Barn here, from 05-04-2013. A message from fellow FordBarn'er H. L. Chauvin. The thread was titled: "B Distributor in a Model-A and how to set the timing perfect?" Mr. Chauvin stated: "This may not be what you where looking for, & some may disagree, however, the following is a vintage detailed description from an original copy of: 'Motors Handbook of Specifications, Interchangeable Parts Service Instructions for 1934'......which covered many specifications for most automobiles made in the US from 1927-1934." I don't know how to quote the thread and place it here in my message. But it should be easy to find in the archives like I did. I could not believe how easy it was to time the distributor after reading the vintage instructions! The only change I made was to set the gap at .020 and not .018.

I hope this might help.


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Old 09-21-2020, 09:20 PM   #22
DBSHELTON
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Default Re: B Distributor Initial Timing

OK, since it will be raining for the next few days, I decided to go ahead and install my new Snyder 6:1 head. After I got everything apart and all cleaned up, I wanted to find actual TDC since it is real easy with the head off. Sure enough, after getting it all setup and checked, the timing mark was 3 1/2 degrees retarded. Kinda surprised that the Timing Dimple on the new laminated cam gear is that far off. Now I feel much better knowing that everything "Jives"! So there is another 3 1/2 degrees of advance I was leaving on the table for the B Distributor.
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Old 09-22-2020, 07:16 AM   #23
aermotor
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Default Re: B Distributor Initial Timing

This may be off topic, but how do I set up a Mallory distributor? The timing cover appears to be the same as an A cover and the Mallory advance appears to be the same as a B distributor. The piston is at TDC with the pin dropped into the flywheel dimple and that is the way things set now. BTW, I had a distributor drive shaft made to put the slot in the center in order to mesh with the Mallory distributor.

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Old 09-22-2020, 05:55 PM   #24
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Default Re: B Distributor Initial Timing

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Originally Posted by DBSHELTON View Post
OK, since it will be raining for the next few days, I decided to go ahead and install my new Snyder 6:1 head. After I got everything apart and all cleaned up, I wanted to find actual TDC since it is real easy with the head off. Sure enough, after getting it all setup and checked, the timing mark was 3 1/2 degrees retarded. Kinda surprised that the Timing Dimple on the new laminated cam gear is that far off. Now I feel much better knowing that everything "Jives"! So there is another 3 1/2 degrees of advance I was leaving on the table for the B Distributor.
If the head is off like during assembly, I never use the timing pin. It is much easier to use the valves on #4 cylinder to get TDC on #1. Let me explain:
#4 is at TDC after the exhaust stroke at the same time #1 is TDC on compression. At the top of the exhaust stroke, the intake valve begins to open 7 1/2 degrees BTDC and the exhaust closes 4 1/2 degrees ATDC. That means that at TDC, both valves are open, the inlet a little more than the exhaust. If you set the motor with both valves open (equally), you will be 1 1/2 degrees BTDC. At this point, the valves are "rocking". That is, if you turn the motor a little forward, the inlet valve will open more and the exhaust will close more. Go back the other way and the reverse happens.
If you stop the motor with the inlet valve a little more open than the exhaust ON #4 CYLINDER, #1 is very close to TDC and your are ready to set the cam on the distributor shaft. Even with a wildest guess at which valve is more open, you will be within a degree or so of TDC - plenty near enough when you consider that while driving, we change the timing by up to 40 degrees according to ear.
These timing angles are crankshaft degrees.
I always instal a timing scale on the front of the engine and put a mark on the front pulley at this stage and never use the timing pin even if I do have to check the timing (VERY rare).
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Old 09-23-2020, 05:14 AM   #25
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Default Re: B Distributor Initial Timing

After rechecking everything the cam gear dimple is only about 1 1/2 degrees off. I do feel much better knowing that TDC is marked on the pulley with a scale using the piston stop method. Much easier using a timing light like a more modern car.
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Old 09-23-2020, 05:21 AM   #26
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Default Re: B Distributor Initial Timing

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Quote:
Originally Posted by aermotor View Post
This may be off topic, but how do I set up a Mallory distributor? The timing cover appears to be the same as an A cover and the Mallory advance appears to be the same as a B distributor. The piston is at TDC with the pin dropped into the flywheel dimple and that is the way things set now. BTW, I had a distributor drive shaft made to put the slot in the center in order to mesh with the Mallory distributor.

John

Never used a Mallory, but I would think you would need some initial timing to start out. I would get a timing scale and maybe start with 12 degrees or so initial and see what the advance curve is. Maybe adjust to 30 degrees total by 2,000 rpm and go from there. Adjust for max timing with no pinging while driving.
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Old 09-23-2020, 07:37 AM   #27
Jack Shaft
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Default Re: B Distributor Initial Timing

30 degrees at 2000rpm with a 6 to 1 head is in the danger area for banging out the center bearing.the engine at 4.2 to 1 compression is way more tolerant of spark advance.
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Old 09-23-2020, 07:43 AM   #28
DBSHELTON
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Default Re: B Distributor Initial Timing

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30 degrees at 2000rpm with a 6 to 1 head is in the danger area for banging out the center bearing.the engine at 4.2 to 1 compression is way more tolerant of spark advance.
True. I didn't know he had a 6:1 head.
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