P-Mag timing

Following Dan Horton’s recommendations, I set the engine advance to a range of 19.6-28 degrees…

The process is very easy, just power up the electrical system, set the prop to the appropriate position, and blow a puff of air into the Manifold Pressure port on the mag. Conveniently I already have flexible rubber tubes connected to these ports, so it was a trivial task.

The black mark on the left was my reference point for setting the timing. The p-mag will operate ~30 degrees from this point.
Using a mirror was the only way to see the LED light on the mags. Green indicates the timing process has completed.