Curtis Fisher Wrote:
"I was having carbureter work done and they said the base timing was too
high, 16 degrees. I know the Motorsport sticker said 10 degrees BTDC and I had
tried that but it ran much better at 14-16 advance, where I left it.
On advice of the carbureter shop I reset it to 10 degrees advance. Not only
does it run worse, it runs hotter, in the 195-200 range. I called Motorsport
and the tech suggested 16 was where he always sets his. Back to 16, no
problems, better cooling, better running."
Curtis,
What is your full advance timing?
What camshaft are you running?
I had recently been experiencing a slight rise in operating temperature with
my Motorsports crate. The first thing I checked was the timing, sure enough it
was off. Too much advance. The distributor was allowing the timing to advance
to about 42 degrees total.
Consulting with wiser members of the list, I have heard that 36 -38 degree
BTDC is where a small block Ford wants to be at full advance.
When I originally assembled my ignition system I went with a full mechanical
(no vacuum) advance system. The distributor was curved to 1 degree at 1000
RPM, 16 degrees at 2000 RPM and 26 degrees at 3000 RPM. With this set up, all
advance was in by 3000 RPM. I static timed it at 10 degrees for a full advance
of 36, all in by 3 grand.
I have heard of guys running as high as 50 degrees full advance and they claim
"that's where it runs the best". I assume that the further you advance a spark
in the cylinder the more you are prone to ping or prematurely ignite the air
fuel mixture. This causes the engine to run hotter.
I would also like to hear other opinions on this subject.
Mike Sutter
'66 Tiger
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