Help me verify my timing procedure, 1981 911SC
 

after researching, this seems to be the procedure for ignition timing on my 81 SC, I think.

1. pull the vacuum hoses to distributor and clamp them shut
2. set the timing at 5 deg BTDC at 950 RPM
3. reconnect the vacuum hoses and adjust idle back to 950

After performing this, I did a quick check with the timing light and after reconnecting the hoses, the car's timing had retarded quite a bit to the left of the Z1 mark. Just guessing, I would say about 5 or 6 degrees. Is this normal?

Thanks!!

Yes, that's the vacuum retard side working for emissions. Pull that backside line and the idle will come up to the 5 BTDC.
Bruce