In article ,
Sylvain VAN DER WALDE wrote:
Mine both ran on standard timing. And didn't pink on 4-star. Perhaps
your timing technique or timing marks were inaccurate? Or perhaps they
just simply needed a de-coke. Also, a slightly weak mixture encourages
detonation.


Static timing wasn't everything. Ignition timing "retarding" devices
(distributor vacuum units) often became blocked, or just failed; and the
automatic advance centrifugal weights' spindle could seize up. The
weight control springs could also weaken, or even be the wrong ones
fitted (exchange distributor).

Absolutely. The advance curve should be checked if pre-detonation is
experienced with the correct static timing. But only if sure the engine
doesn't need a de-coke and the mixture is correct. Also check the
operation of the vacuum unit.

--
*Taxation WITH representation ain't much fun, either.

Dave Plowman London SW
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