Helmet Distributor Timing Adjustment

[SoCalCoupe]

No doubt this question has come up many times but I'm too dumb to find the right search terms.


I have a stock 1941 flathead with a helmet distributor. I'd like to experiment by adding in a bit more timing. I see how the timing adjustment works with the set nut and the tick marks on the passenger side of the car, but I cant tell which way is + timing and which way is - timing. I THINK that the distributor rotates clockwise as viewed looking aft standing in front of the car but I don't know.


If so, it would make sense that to advance timing, I'd loosen the nut and shove the nut (with the interior ring) down, or counter-clockwise to advance the timing.


Perhaps I haven't said this correctly, or even backwards, but any help would be appreciated.


BTW, how many degrees would each tick mark be worth?

[Mart]

The crankshaft turns clockwise. The cam is gear driven at 2:1 ratio so the distributor turns anti-clockwise when viewed standing in front of the engine or car.
So armed with the anti-clockwise rotation, you can surmise that the points base plate needs to go clockwise to advance the ignition.
For a crab distributor with the adjustment screw on the left side of the motor (when viewed from drivers seat) it needs to go downwards to advance and upwards to retard.
For the helmet distributor the adjustment screw is on the right hand side of the distributor so to achieve a clockwise rotation of the points base plate, it has to be moved upwards. Moving it downwards will retard it.
I'm not sure what the lines amount to in degrees, but try one line at a time or half a line and see if detonation occurs. If it does back it off until it no longer occurs.
Mart.

[aussie merc]

im led to believe that 1 line is 2deg on the distributor so that would be 4 deg on crank

[Bored&Stroked]

Always rotate the points plate or housing in the counter direction to how the rotor turns to advance the static timing. There are other ways to increase the total timing - based on which advance mechanisms are inside the distributor. I believe the '11A' mechanisms tend to give the most mechanical advance.

[Ken/Alabama]

Up with it to advance.

[Ziggster]

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These are the instruction from the FoMoCo NOS breaker points I got. Not too much info as they say to use the distributor testing machine, but I thought I would though it out there as I’m going through my parts getting mine ready to fire up.

[Ziggster]

Next.

[Ziggster]

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[petehoovie]