[this never showed up either]
I would just add that the "trial and error" method is more appropriate for
someone who has a solid grasp of the principles involved, and of what he is
trying to achieve (relative to previous performance of the vehicle, etc.),
and for a vehicle that is otherwise properly set up. In Mike's case, I'm not
sure that any one of the three (timing, idle, dwell) is correctly set up as
of yet, and I think Mike would benefit immensely from the real-time feedback
available with the timing light. IMHO.
I'm not "dissing" Mike's abilities, but it is apparent from his questions
that he is relatively inexperienced (at least with MGs).
Perhaps now would be a good time to explain that there are two ways to go
about rotating the MGB distributor. The bracket that holds the distributor
to the engine block has a clamp with a single screw that grabs the
distributor base (this is the "obvious" place to loosen it for adjustment),
but it also has two bolts that connect to the block, and the holes for these
bolts are elongated, allowing for a certain range of adjustment here, as
well (I have opened mine up further with a round file). Experienced B
mechanics will set the distributor timing using the clamp screw ONCE, and
then leave it alone thereafter, since this clamp is designed so as to
function as a nutcracker for the purpose of destroying the distributor
housing, and will do so if overtightened. Subsequent adjustments are made by
loosening the two bolts in the block, and rotating the entire assembly. This
is marginally less convenient (none of the bolts in question are
particularly accessible), but much safer in the long run. If you have the
vernier adjustment (and have been careful to maintain it in the middle of
its range), this step might be unnecessary in many cases.
--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the primer red one with chrome wires
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