https://www.britishcarforum.com/bcforum/u...es_c#Post305681
Here's my rather odd way of finding approximate timing... worked for me.
"Pulled the valve cover off, jacked the rear left wheel off the ground. Connected the timing light to #1 wire.
Turned over the engine by hand, until the timing marks were at or just before BTDC, and valves 7/8 were both rocking, as suggested above. GREAT advice, very easy. (FYI, at TDC of the exhaust stroke, 7/8 are both dead still, so this is a pretty definitive check, but I did double-check with a piece of solder down the spark plug hole, to confirm that the piston was at the top of its travel.) Confirmed, my TDC is at approximately 12 o'clock.
Now for the confusing part. With the timing light on #1 wire, and the key in the 'run' position (to energize the coil) I continued to turn the rear wheel by hand, very slowly, until the timing light fired. (So I knew the rotor should be lined up with the #1 post in the distributor cap.) Went and pulled the cap... and the rotor looked like it was maybe 20deg *past* the post. Repeated this several times, same result. I have no explanation for this. But
in any case, I used an imaginary line about 20deg behind the rotor, and lined that up with the #1 post with the timing marks set to 10 BTDC.
I barely touched the remote switch I've been using (for timing etc.) and the motor immediately sprung to life, and settled to a nice idle. I put the timing light on it, and it was maybe 20+ BTDC... far left of the scale, in any case. I advanced it toward 10-12 BTDC, and the idle worsened slightly and slowed. I'll follow the correct tuning settings tomorrow.
So, I have no idea why the distributor seems to fire once the rotor is already well past the post, rather than (what my eyes tell me is) a straight line. But, once I let go of what my eyes see, and trust only what the timing light tells me, everything seems fine."