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beepbeep beepbeep is offline
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Join Date: Jun 2001
Location: Sweden
Posts: 5,565
Usually, you set up idle ignition timing quite low at idle RPM target (like 12 degrees @ 900 RPM) and raise it just below (like 18 degrees @ 800 RPM). As ignition is advanced, engine will pick up revs. So ignition advance at 800 RPM is used as guard against idle stalling.

Leaning out the mixture usually sends NOx values up but HC values down. If US emission laws don't care about lambda and NOx, you can lean out the idle until HC goes down. Also, you can raise idle RPM to 1000 revs or so (1250 seems to be max) in order to heat up the cat more.

Those tricks won't fly in Europe (they check NOx, lambda, HC and CO here) but might work in your case.
Thank you for your time,
Old 10-10-2009, 05:13 PM
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