If I understand correctly, running on can be a consequence of running too much advance. Now my engine may not be technically running too much advance compared to what people run on Zs (there is no pinking occurring for sure) but there is a clear running on issue.
I'm just going from past experience here - when the engine/ignition timing was originally set-up last year, it had a tendency to run on quite badly. Mark Rayner adjusted it slightly (using timing light) taking 1-2 degrees out of the advance it was running. This alleviated the problem.
When rolling roaded, as I mentioned above, Ric Wood advanced it again a couple of degrees, basically to where it was originally. This reintroduced the running on, which can be several seconds worth of less than subtle convulsions in this case!
If somebody wants to tell me that is fine and acceptable, then go ahead. I'll admit to knowing very little about the technicalities of ignition timing etc etc. I just don't particularly like my car chucking a fit everytime I turn it off.
Just to be clear again when I said retarding the timing, I meant running a little bit less advance. Forgive my technical illiteracy if people though I meant something else.
I had never heard of the throttle blip approach to stopping running on. Seems to be mentioned in various places on the web as a common solution. Although it does seem like a bit of a sticking plaster rather than addressing the underlying cause.
