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Old 07-18-2008, 01:25 PM
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You'll probabily find that you are for the most part "crusiing" on the idle/idle transfer slot circuit as opposed to the main jets. (the main jets don't come into play untill about 40MPH +/- depending on the rear gear ratio cruising rpm) To trim the cruise try adjusting the size of the idle feed restrictions with small V shaped pieces of mig wire/ guitar string wire.

Take the idle AFR gauge reading with a grain of salt.
A motor with a high overlap cam will cause the AFR meter to show a false lean(er) ratio as the motor's incomplete combustion at idle (rough idle camshaft timing)
allows free oxygen and unburned fuel to pass through the motor to the exhaust.
The o2 sensor does not know the difference. It only senses free left over oxygen in the exhaust. A manifold vacuum gauge is still your best tool for setting the idle. Most carburated engines need a true AFR somewhat richer than 14.7 at idle for good/best idle quality and throttle response.
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