> First of all: The factory manuals or the group with their accumulated
> experience and all working together would be the best sources as to what plate
> (or maximum advance) should be used.
Jim sounds like a nice guy, and I'm sure he knows all about distributors. But
he doesn't know Triumph manuals !
> Secondly: Keep in mind that distributor advance is half of the engine advance.
> In other words, if the max distributor advance is 10 degrees, that would
> translate into 20 degrees of engine advance.
Good point, but some manual entries are given in crankshaft degrees instead of
distributor degrees. And, I know of at least one Triumph manual (Stag, not
TR3A) that specifies crankshaft degrees but the numbers given are in distributor
degrees !
> Fourthly: The next question is - - If there is a vacuum advance, at a cruise
> configuration of 2750 engine rpm, how much vacuum advance is obtained.
As a general rule, there will be more than enough vacuum at mid-range cruise to
obtain the maximum vacuum advance. This is the third number (in distributor
degrees) in the three number sequence (eg 7-14-10).
> If the
> centrifugal advance cranks in too much and then the vacuum advance adds some
> more, one can get too much advance.
Yes indeed, which can damage the engine.
Randall
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