Autom. advance spark timing

[Werner]

Guten Abend.

Is there a difference between Bratton's mechanical centrifugal ignition ($225) and Don Snyder's ($203)?
Does the device work very well?
What disadvantages are possible?

Many thanks in advance!

[29spcoupe]

They are one in the same.

[Y-Blockhead]

Originally Posted by Werner

Guten Abend.

Is there a difference between Bratton's mechanical centrifugal ignition ($225) and Don Snyder's ($203)?
Does the device work very well?
What disadvantages are possible?

Many thanks in advance!

They are the same made by Nu-Rex and are a copy of the original Phillips.

https://www.fordgarage.com/pages/phillipsspark.htm
https://www.fordgarage.com/pages/nurexadvance.htm

IMO it works very well. One "disadvantage" is in some situations your timing may be too advanced. In this situation I simply retard the advance lever some.

I set my timing so "0" advance is ~ ½ way down so I can retard the timing if needed (say on a hill)l. My timing with the Nu-Rex is set with the advance all in at 30°.

[nkaminar]

Blockhead, Thanks for the links. This is a pretty ingenious device. I learned something today. I am going to stick to my hand adjustment just because I am a control freak.

[CT Jack]

The Bratton & Snyder centrifugal advance units are the same except for the price. I have used this distributor advance unit and it worked well. Changes in engine speed causes a gimbled disk attached to the distributor drive shaft to change its angular orientation. As the the angle of the rotating disk changes it mechanically rotates the distributor point mounting plate.
I replaced this unit with an FS Zipper distributor which has a Model B type centrifugal advance along with a Petronix electronic ignition module. This system makes driving a Model A a joy. The advance retard control lever on the steering column is locked so when you go up a hill you just use the gas pedal.

[Werner]

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Good morning,


yes, this is a mechanically simple and beautiful system!



I was thinking of an invisible electronic advance ignition, but that doesn't work with my original pop-off switch, which I'm very proud of.



The most practical solution seems to be that the distributor from the B Model can be easily inserted into the A motor?



Therefore I will try to find a good used B distributor.

[alexiskai]

Originally Posted by Werner

I was thinking of an invisible electronic advance ignition, but that doesn't work with my original pop-off switch, which I'm very proud of.

The most practical solution seems to be that the distributor from the B Model can be easily inserted into the A motor?

Therefore I will try to find a good used B distributor.

The B distributor doesn't accept the original wire that runs from the pop-out switch to the lower plate. On the B, a wire comes down from the ignition and terminates at a simple screw. If you want to keep your pop-out switch and cable in original condition, but also have automatic centrifugal advance, the Nu-Rex is your only option.

[Werner]

Alexis,

thank you very well, that's important to know.
The pop off switch must remain installed. The cable change to an other doesn't matter.

But I do not know how. I have an electrical schematic for my A, but can't find one to compare for the B ignition.


Any idea how to change the wires?

[alexiskai]

Originally Posted by Werner

Alexis,

thank you very well, that's important to know.
The pop off switch must remain installed. The cable change to an other doesn't matter.

But I do not know how. I have an electrical schematic for my A, but can't find one to compare for the B ignition.


Any idea how to change the wires?

The schematic is the same. You remove the cable armor and the threaded terminal at the distributor end of the wire. Then splice on more wire if you need it, plus a flag terminal at the end. For comparison, here is the stock Model B ignition wire, which is wrapped in a loom together with the high-voltage wire from the coil.

[Werner]

Thanks, Colin, for your guiding help.

Changing the wiring is therefore not a problem. Good.

But after reading further here, another question arises:

The automatic "B" distributor has only an adjustment range of approximately 20° advance. Therefore the "B" engine is then always started with about 15° of ignition advance.



With model "A" I can use the hand lever to set the ignition point back to <0 degrees for start.

But the "B" distributor does not have this option. But then my "A" engine starts with a lot of advance. This can be bad for the hand crank and starter.

Or is it possible to convert the "B" distributor also to a manual adjustment?

[ursus]

I haven't seen it done, but it might be possible to convert it to manual adjustment albeit within a limited range. The upper plate where the points and wire from the coil attach has a tab with setscrew that is marked with gradations allowing for a range of +/- 10 degrees of adjustment from the initial 19 degrees of advancement. This would require some unique fabrication to achieve this modification.

The 15 degrees of initial advance that you cited was an error in the Ford company documents. It is actually 19 degrees.

[Werner]

Guten Abend Ursus.

Danke, that would be a nice option. I could purchase the B distributor shown below. There are probably a lot of A drivers here who have already done that like this, I hope.

Please write it now.

[alexiskai]

I have both the Nu-Rex timing device (installed, running) and a B distributor (for the project car). The B distributor is best used for high-compression heads ≥6:1, where the compression puts a reduced maximum on the total timing.

The centrifugal advance on the B distributor permits only 15° mechanical advance (in addition to whatever your initial timing setting is). So you could use it on a 7:1 head with initial timing of 7° and total timing of 22° and it would be fine. If you have a stock 4.2:1 head, you need all the advance you can get. I think a B distributor in that scenario would be a mistake.

Regarding the fitting of a B distributor plate with a ball mount for manual spark advance... seems like a bad idea. The B plate wasn't designed to be moved back and forth multiple times a day. You might bend the mount point or the tabs that support the plate in the body.

[Werner]

Originally Posted by alexiskai

... Regarding the fitting of a B distributor plate with a ball mount for manual spark advance... seems like a bad idea. The B plate wasn't designed to be moved back and forth multiple times a day. You might bend the mount point or the tabs that support the plate in the body.

OK, that's helpful advices. Who teach me that the simple NuRex centrifugal ignition is the best conversion for automated advance ignition.

They hurt, the high additional costs. The freight alone has exploded to almost 100.00 plus 7% EU customs and 19% VAT. Ouch!

But every true love has always been particularly expensive...

I would like to thank everyone again for the many patient explanations!

[alexiskai]

Originally Posted by Werner

They hurt, the high additional costs. The freight alone has exploded to almost 100.00 plus 7% EU customs and 19% VAT. Ouch!

Use Nu-Rex's contact form and just ask whether they have any tips on purchasing one of the timing devices in Germany. You never know what they might say. When I told them I was making a video about the device, they loaned me one to demonstrate with, free of charge. Very nice people.

[Synchro909]

Originally Posted by Werner

They hurt, the high additional costs. The freight alone has exploded to almost 100.00 plus 7% EU customs and 19% VAT. Ouch!

Werner,
At least you can get stuff from the US. We can't. USPS doesn't send mail to this part of the world any more - not even the MAFCA magazine. I don't even look at the "For Sale" section of the swap meeting part of this forum because I wouldn't be able to get anything I might buy.
If you'd asked me a year ago whether I would be affected by that, I'd have said "No." but I and everybody else here and many in the US are. I have a friend who married an American lady and for her, the exchange of gifts is no longer possible. That is just one tiny affect of this.
BTW, I wouldn't use a B distributor. I strongly suspect the reason B blocks are so prone to cracking is not solely due to their thinner castings but also because the distributor doesn't work properly and they run retarded, causing them to over heat, then crack. I have 3 of them and while they all look good and bushes and shafts etc are good, they don't advance properly. IMO, the best place for a B distributor is in the trash.

[jack backer]

My findings with the B distributor are the same as Synchro909,They dont 'map' (timing curve as viewed with a timing light) well and are erratic. The nurex gyro advance is adequate for a stock engine which is tolerant of timing deviation.If you decide to raise compression be advised the engines tolerance for improper timing decreases,and a precise advance curve is desired,like the FSI distributor.

[Werner]

Thank you all for this additional informations!


Colin his hint came too late, at the time of reading Snyder's had already shipped the centrifugal ignition adjuster.

In the meantime, I have also come to the realization that the B distributor is only half the story and requires a lot of attention and keen ears while driving.

I'll install the technology next week and report back.


Special question to Synchro: Why is it a problem for you to get spare parts etc. from the USA?
.

[alexiskai]

I'm still going to try to use my B distributor, but I also have a digital timing light and tachometer, so I can verify and adjust my timing curve down to single degrees. If you don't have that gear, I wouldn't try it.

[eagle]

IMO there are people who can't hear their engine, auto advance is fine for them, although I'm not sure I'd trust some of the gizmos I've seen mucked up to an A engine. If you can hear the engine, setting the timing lever is second nature after a bit. I don't even think about it when driving, that's automatic enough for me. Heard about someone who had an electric servo motor running the advance, and a tach sensor on the front pulley, all hooked up to a laptop computer that he kept on his seat, talk about a kluge.