Timing fine tuning - timing from the advance marks

[jamesandtheopenroad]

Found this on the web which I think is really interesting. http://www.vw-resource.com/tune-up.html#svda

It basically says how the initial timing (eg - on a DG 5btdc) is preliminary, and to tune the engine properly, you should set the timing from the advance marks and then take the initial timing from where the btdc mark ends up.

Now, I know this is from an Aircooled point of view but I wondered if anyone has done anything similar and if so, how it affects the drive of the van?

[California Dreamin]

It's called a compromise......a compromise between what VW originally intended and how everything actually runs on a 30 year old motor with a worn distributor.
I'm guessing that under normal circumstances setting at 5 degrees BTDC will result in over advancement at higher revs due to worn distributor springs etc.

Martin