Tweaking AFR at idle, how much fuel to pull?
#1
Tweaking AFR at idle, how much fuel to pull?
I'm running Holley EFI, although I don't see that it matters really. Used a base tune and have been making the necessary changes over the past few months. Ilde quality sounds and feels great, but I feel it's a little rich. Just by smell. Old tune/engine never stunk up the garage with the door open. ANYHOW....to my question. Idle AFR is about 13.5. How much change is a good starting point? 13.7? 14? 14.7? Don't wanna go nuts and lean it out, but also don't wanna make tiny changes that won't actually affect anything.
I've read a lot and people seem to idle all over the place, but typically conversations seem to start with an AFR at idle around stoick/14.7
I've read a lot and people seem to idle all over the place, but typically conversations seem to start with an AFR at idle around stoick/14.7
#2
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Re: Tweaking AFR at idle, how much fuel to pull?
I would lean it out some, try 14.1 as a starting point. For a good idle need to run a little richer then stoich.
RBob.
RBob.
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Re: Tweaking AFR at idle, how much fuel to pull?
AFR value at idle is not trustworthy so just give the engine what it wants. The number will be what it will be.. The fuel smell can be helped by paying attention to injection end angle.
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Re: Tweaking AFR at idle, how much fuel to pull?
I guess I should mention that if it is still batch fire then you have no control of injector end angle. Don't want to cause you to waste your time.
#9
Re: Tweaking AFR at idle, how much fuel to pull?
I guess I should mention that if it is still batch fire then you have no control of injector end angle. Don't want to cause you to waste your time.