Re : 216/235 & 261 Ignition Timing
A couple of years ago my 1953 pickup with 1954
235 ran okay when timed on the BB but had a lack
of pulling power under load. Vacuum and
mechanical advance worked, the heat riser worked
and the exhaust system was clear. If pushed at
low RPM it would backfire through the carb like
a cold engine, even though fully warmed up.
Since backfire and lack of power can both be due
to lean mixture, we installed a rebuilt carb and
verified the float level, without finding any
improvement.
Since lack of power under load can also come
from a weak spark we replaced the spark plugs,
plug wires, rotor, cap and coil. Again, there
was no improvement.
Still looking, we decided to try a little more
spark advance. We advanced it “some,” drove it
and found a real improvement. Adding advance
twice more gave a huge improvement. She pulls
like a locomotive and the backfire is gone. The
timing light shows we are about 1.3 inches
advanced from the BB, we guess it to be 15
degrees more.
This timing method takes me back to the 1950s
when a kid with no timing light could do a
decent job by advancing a little and test
driving until it started to tinkle, then retard
it a little. If you then found it started hard
due to too much advance, you backed it off just
a little.
Dennis McGillis
___________
--- Original Message ---
Thu Jul 4, 2013 9:40 pm (PDT) . Posted by: "Nate" vwnate1
Hi Luke ;
Never , EVER time these engines to TDC ! doing so will cause them to run hot
and cause rapid top cylinder wear .
_ALWAYS_ use ONLY the BB & pointer , set at 600 RPM or less and check , there
should be no vacuum signal at this engine speed .
You're correct , the improvement in power and smoothness is marked when timed
to ball & pointer .
I hope this helped .
-Nate
[Non-text portions of this message have been removed]
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