So I am trying to log my boost from my AEM gauge.
AEM says it should be (voltage*12.5 -6.25)- barometric. for me I am at sea level should be 14.7.
How the hell do put that into the multiplier. i would assume the offset would be -14.7?
DATAQ equations help
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Renovelo
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Re: DATAQ equations help
Which AEM gauge are you using? Do you have a link to some online documentation?
To answer your question, this equation can be seen as: Y = (12.5*X - 6.25) - 14.7. If you recall from algebra, this is no different than: Y = 12.5*X - 6.25 - 14.7, which can be simplified to: Y = 12.5*X - 20.95. Therefore, the scalar would be 12.5 and the offset would be -20.95.
Now, the reason for asking which gauge you're using is because this equation seems incorrect. Most wideband gauges output a 0-5V analog signal. Inputting 0V into the above equation gives an A/F ratio of -20.95 which doesn't make sense. Inputting 5V gives an A/F ratio of 41.55 which also doesn't make sense. The "usable" range of this sensor would be ~2.5-3.3V which really doesn't make sense.
To answer your question, this equation can be seen as: Y = (12.5*X - 6.25) - 14.7. If you recall from algebra, this is no different than: Y = 12.5*X - 6.25 - 14.7, which can be simplified to: Y = 12.5*X - 20.95. Therefore, the scalar would be 12.5 and the offset would be -20.95.
Now, the reason for asking which gauge you're using is because this equation seems incorrect. Most wideband gauges output a 0-5V analog signal. Inputting 0V into the above equation gives an A/F ratio of -20.95 which doesn't make sense. Inputting 5V gives an A/F ratio of 41.55 which also doesn't make sense. The "usable" range of this sensor would be ~2.5-3.3V which really doesn't make sense.
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oryharam
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Re: DATAQ equations help
its an AEM digital boost with output.
the equation comes directly from aem. i think the voltage range is actually 0 - 4.5 on this guage.
in my head it didnt seem that easy but i guess they wrote it the way they did to make sure you deduct your barometric properly.
Ill give this a run hopefully comes through.
the equation comes directly from aem. i think the voltage range is actually 0 - 4.5 on this guage.
in my head it didnt seem that easy but i guess they wrote it the way they did to make sure you deduct your barometric properly.
Ill give this a run hopefully comes through.
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Renovelo
- Site Admin
- Posts: 295
- Joined: Thu Aug 08, 2013 7:02 pm
Re: DATAQ equations help
Do you have an actual model number for your gauge? For example, here is a link to the AME 30-0300 X-Series UEGO Gauge: https://www.aemelectronics.com/sites/de ... 0Gauge.pdf
On page 10, you'll see the following equation: AFR = (2.3750 * Volts) + 7.3125
This same equation is also used in AEM's 30-4900 gauge (pg 17): https://www.aemelectronics.com/sites/de ... _Gauge.pdf
Assuming a 0-5V output, this gives an AFR output of ~7-20 which is more reasonable.
On page 10, you'll see the following equation: AFR = (2.3750 * Volts) + 7.3125
This same equation is also used in AEM's 30-4900 gauge (pg 17): https://www.aemelectronics.com/sites/de ... _Gauge.pdf
Assuming a 0-5V output, this gives an AFR output of ~7-20 which is more reasonable.