Well, I had set the point gap and static timing correctly and the car ran
better than before, but it still felt retarded. I think this engine has
a cr of 8.3 to 1. Should it run fine on 87 octane unleaded? It does,
except for a little occasional run on because of carbon deposits in the
head and on the pistons. I might try the thin stream of water into the
carbs treatment to decarbonize. Anyone ever do this with SUs?
Anyway the centrifugal advance seemed to be working, so I suspected the
vacuum advance wasn't, what with a 35 year old diaphragm and all. I
tested the unit and it seemed fine. _Then_ I started the car and checked
for vacuum at the vacuum pipe. Nothing. So after cutting the pipe in
several pieces, I expunged the clogged segment and spliced the thing back
together with some rubber vacuum _tubing_. I couldn't locate a supplier
for this tiny metal tubing yesterday. Seems to be working better. But I
wonder if the advance curve is correct. My shop manuals don't mention
anything about it. For example a set of curves for different vacuum
levels plotting rpm vs. advance would be cool.
Any advice or suggestions would be appreciated.
Kevin Sullivan
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