I am not a big fan of static timing. In fact. I am not a fan of blindly
following any published timing recommendations. The reason is that there
are so many variables that no one timing recommendation works for all cars
even if they are "identical." When I took the A's dizzy apart the springs
were loose enough so that static timing could have swung 5 degrees easy.
Once the engine was running, the weights pulled the springs tight and
timing stabilized so the only down side was a slight loss of total advance.
Not a real issue for a daily driver but the point is that static timing it
would have been a bloody waste of time. Any play in the system can have
the same effect since looseness can effect the running system differently
than the static system.
As far as timing goes, the most important number is total advance. For
most engines, this should be in the low to mid 30's. 35 degrees is a good
place to start for most engines. This is difficult to measure without an
expensive timing light so I still recommend timing by ear. Go out on a
good hot day and run the car hard. Then find a moderate hill and
accelerate hard from low rpm up to about 4k. If you hear knocking, retard
the ignition. If you don't advance until you hear a knock then back off.
You will be surprised how free your engine runs after this. Factory specs
are set for worst case conditions. The car with the sharpest points in the
combustion chamber with the highest compression ratio and the least
accurate timing marks running on the worst gas won't self destruct at this
level. It is almost always too late for optimum performance. Your car
will be faster, run freer, and run cooler with optimum timing. I have been
timing cars like this for 25 years and have never had a mechanical failure
due to early timing. I have never owned a timing light.
One more thing, according to the literature that I have read, light knock
is not destructive. I ran a Chevy Blazer for years with a light part
throttle knock with no apparent damage. If I backed off the timing the gas
mileage went from merely godawful to downright horrendous. I was a
teenager at the time so my good luck was not due to conservative use of the
throttle.
I think that the reason that LBC's stuck with recommending static timing
had less to do with the superiority of the measurement and more to do with
their slow acceptance of postwar technology and their general opinion of
the basic mechanical intelligence of the colonies.
Regards,
Bill Eastman
61 MGA running great after giving the dizzy "a little twist or two"
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