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Old 09-12-2011, 05:20 PM   #1
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Default X fuel = 1:1 afr?

What is X???

Is there a way to mathmaticly remove or add fuel? I know there is no perfict math but anything to get my closer as randomly pulling fuel the drving the car is not working.

example: i'm at 10.234ms of fuel at 3000rmp 180kpa and seeing 9.8:1 and need to be at 11.5:1.

555cc injectors.
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Old 09-12-2011, 05:36 PM   #2
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Calibrate your IAT sensor settings like I told you or you're going to do this every time you drive the car when the weather drops 5*f.
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Old 09-12-2011, 05:37 PM   #3
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weight.

12.5:1 means that for every kg of air, 0.08 kg of fuel is mixed in and vaporized.
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Old 09-12-2011, 05:56 PM   #4
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Quote:
Originally Posted by hustler View Post
Calibrate your IAT sensor settings like I told you or you're going to do this every time you drive the car when the weather drops 5*f.
And like i told you my IAT table is running the y8s vales like every person with a miata adaptronic and a GM IAT. Every morning this week i have checked what the ecu see vs ambient temps before starting the car and it has been spot on. Afrs are that same at wot all week weather it was 70* out open road driving in the morning or 95* and car has been sitting in traffic. You can't calibrate it like MS with the cool 3 data points.

Not discressing or ignoring your advice, i spent a few hours Sat looking into it.

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Originally Posted by Braineack View Post
weight.

12.5:1 means that for every kg of air, 0.08 kg of fuel is mixed in and vaporized.
2300 loaded, any math for kg to ms?
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Old 09-12-2011, 06:04 PM   #5
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I didn't know you did that, it was a long weekend.
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Old 09-12-2011, 06:49 PM   #6
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I didn't know you did that, it was a long weekend.
Did the same with water temps before you saw the car 2 weeks ago. I triple checked all the calibration and correction tables i could vs y8s info and other maps from similar cars.
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Old 09-12-2011, 07:04 PM   #7
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close enough way:

DAFR: desired AFR
AFR: measured AFR
PW: pulsewidth
NPW: new pulsewidth

change in fuel multiplier ~= (AFR-DAFR)/AFR
(will be negative if you need to remove fuel)

you multiply this by your PW to get the amount to ADD to the PW.

so if you want to get from 9.8 to 11.5....

(9.8-11.5)/9.8 = -.173

NPW = PW + PW*(-.173)

or in your case:

NPW = 10.234 + 10.234*(-.173)

NPW = 8.464 ms

for the Adaptronic, you have a VE table. Just replace NPW and PW with NVE and VE.
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Old 09-12-2011, 07:41 PM   #8
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Quote:
Originally Posted by y8s View Post
close enough way:

DAFR: desired AFR
AFR: measured AFR
PW: pulsewidth
NPW: new pulsewidth

change in fuel multiplier ~= (AFR-DAFR)/AFR
(will be negative if you need to remove fuel)

you multiply this by your PW to get the amount to ADD to the PW.

so if you want to get from 9.8 to 11.5....

(9.8-11.5)/9.8 = -.173

NPW = PW + PW*(-.173)

or in your case:

NPW = 10.234 + 10.234*(-.173)

NPW = 8.464 ms

for the Adaptronic, you have a VE table. Just replace NPW and PW with NVE and VE.
Love you, will try this, my only problem is 3k to 6k being to rich, rest of the map is great. I also no know thing about VE tables you speak of.
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Old 09-12-2011, 09:11 PM   #9
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The just select the 3-6k columns and execute the math function on those columns. The math function would be to multiply by .85 to reduce fuel 15%
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Old 09-12-2011, 11:25 PM   #10
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practically speaking, yes you can subtract from 1 (or 100%) and use that value and the "multiply cells by" function in the fuel map.
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Old 09-13-2011, 01:09 AM   #11
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Thread is void. enrich and go open loop was at 24%, removed that and added some fuel back and gtg
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Old 09-13-2011, 01:15 AM   #12
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Yay jizzm
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