RE: Ignition timing.
Posted in the other forum, so I might as well repeat it here:
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There really is not a general timing because engines are so different.
Low compression, low specific power engines on pitts muffler 28-30°
high compression low specific power, 26°-30°
high specific power engines, high compression, 24° - 26° (18° - 24° on tuned pipe)
In general, with tuned pipe or canister use, time 4° later than with pitts mufflers
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