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equation for finding lambda difference? parker or davis *cough, cough*

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equation for finding lambda difference? parker or davis *cough, cough*

Old 07-25-2005, 11:37 AM
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Default equation for finding lambda difference? parker or davis *cough, cough*

what's the equation to manually find the difference between your current afr and target afr? i had it saved some where and haven't needed it for a while, i can't seem to find it. figured i'd post up instead of pm'ing you guys so that everyone can see it, someone else may need it also.
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Old 07-25-2005, 12:39 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

((ActualAfr / TargetAfr) - 1) * 100 = PercentDifference

Example:

1) 10.5 / 12.1 = 0.8677685950413223140495867768595

2) 0.8677685950413223140495867768595 - 1 = -0.1322314049586776859504132231405

3) -0.1322314049586776859504132231405 * 100 = -13.2

...So you take -13.2% out...
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Old 07-25-2005, 12:59 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

that's what i thought it was, but it just didn't seem right to me. for some reason i was thinking injector size was a variable in the equation.
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Old 07-25-2005, 04:04 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

Naw, since you've already got your physical AFR (already calculated pulse durations with whatever size injectors you're using) you are just calculating what the difference in percent you would need to add or subtract to achieve the target AFR under the same conditions..
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Old 07-25-2005, 08:36 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

"Cough cough" thanks Mr. Davis
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Old 07-25-2005, 09:10 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

Originally Posted by tranceminister
"Cough cough" thanks Mr. Davis
haha... back to basic algebra we go.
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Old 07-26-2005, 01:55 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

haha, I like how Parker carries it out to 10k decimal places. :P
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Old 07-26-2005, 01:58 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

what dave, you mean you don't add 13.22314049586776859504132231405% when tuning?
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Old 07-26-2005, 07:25 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

Originally Posted by leed
haha, I like how Parker carries it out to 10k decimal places. :P
Hahah.. copy and paste from calc32.exe.
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Old 07-27-2005, 01:40 PM
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Default Re: equation for finding lambda difference? parker or davis *cough, cough*

Originally Posted by projekteg
what dave, you mean you don't add 13.22314049586776859504132231405% when tuning?
Amateurs!
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