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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
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Also, I have a digital AFR gauge hooked to a wideband O2 at my new B&B header. I notice that my warm AFR's are running at about a 13.5 AVG. Maybe this is a little low?? And, because it's a little low, it's a little rich - - - - - - soooooooooooooooo, when the AAR introduces the extra air, it mixes with a rich fuel mixture and make the idle a little higher than necessary???????

13.5 AFR, I presume you mean at idle, really isn't all that rich. In fact, it's the opposite of what you're thinking. The lower the AFR, the richer the mixture. So, perhaps with your idle AFR where it is, the extra air is making it leaner still and raising the idle. I don't remember, but I think 14.-something is the stoichiometric optimum for lean best idle/fuel economy.

Try adjusting your idle, and if you have acess to someone who can test your exhaust emissions, it will help to make sure you're in the ball park on CO%, and ultimately AFR's. Oh, and don't forget to check your ignition timing to make sure it's spot-on. That in itself can result in higher idle rpms.
Old 11-04-2008, 06:29 PM
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