P8, ana3 and set lambda parameters

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Peter15
Posts: 19
Joined: Sat Nov 26, 2022 3:56 pm
ECU Model: P8 Pro
Distributor: Ebay
Firmware Version: V35

P8, ana3 and set lambda parameters

Post by Peter15 »

Hi guys
I am creating a map on p8 and I use a Aem uego a/f ratio
and in the lambda parameters table I have to report the 0-5v Aem data but I have a difficulty
1) the p8 have the value from 8 at 16 while in Aem max value is 18
2) in p8 the values ​​start from 16 and go down to 10 while with Aem it is reversed they start from 8.50 and go up to 18
3) in p8 there are 20 values while Aem are 17.

how can I adapt the instrument to this ecu?
Thanks
Rob Stevens
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Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: P8, ana3 and set lambda parameters

Post by Rob Stevens »

The output from the Aem is probably a straight line. plot it on a graph and just pick 20 points and input your info into the P8
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: P8, ana3 and set lambda parameters

Post by stevieturbo »

as above, it'll just be a straight line. So just figure it out from there.
Peter15
Posts: 19
Joined: Sat Nov 26, 2022 3:56 pm
ECU Model: P8 Pro
Distributor: Ebay
Firmware Version: V35

Re: P8, ana3 and set lambda parameters

Post by Peter15 »

ok thanks, i'll try 🙏
Peter15
Posts: 19
Joined: Sat Nov 26, 2022 3:56 pm
ECU Model: P8 Pro
Distributor: Ebay
Firmware Version: V35

Re: P8, ana3 and set lambda parameters

Post by Peter15 »

I found the formula:
Afr=(2,3750× volts)+7,3125
Lambda=(0,1621×volts)+0,4990
now it's easy
katana
Posts: 455
Joined: Sun Jan 27, 2013 6:08 pm
ECU Model: S60 Pro
Firmware Version: 29

Re: P8, ana3 and set lambda parameters

Post by katana »

Peter15 wrote: Mon Dec 05, 2022 4:51 pm I found the formula:
Afr=(2,3750× volts)+7,3125
Lambda=(0,1621×volts)+0,4990
now it's easy
I'm assuming that is particular to AEM only, as other kits using 0v - 5v can have ranges from, as low as, 7:1 to high as 30:1.

Just for giggles I used your formula to check petrol stochiometric point (14.7:1) assuming a 0-5v range and it being midway in the range -
so, (2.375 x 2.5v) + 7.3125 = 13.25 : 1 AFR. Assuming scale was 1-5v that puts mid @ 3v. Now put that into the equation and it
comes out to 14.4375:1 - close but no cigar. It would seem that you must, a) know the voltage output range used and b) the scale range used
as without these drawing any line or conclusion maybe way off.
Peter15
Posts: 19
Joined: Sat Nov 26, 2022 3:56 pm
ECU Model: P8 Pro
Distributor: Ebay
Firmware Version: V35

Re: P8, ana3 and set lambda parameters

Post by Peter15 »

Image
katana wrote: Tue Dec 06, 2022 8:09 am
Peter15 wrote: Mon Dec 05, 2022 4:51 pm I found the formula:
Afr=(2,3750× volts)+7,3125
Lambda=(0,1621×volts)+0,4990
now it's easy
I'm assuming that is particular to AEM only, as other kits using 0v - 5v can have ranges from, as low as, 7:1 to high as 30:1.

Just for giggles I used your formula to check petrol stochiometric point (14.7:1) assuming a 0-5v range and it being midway in the range -
so, (2.375 x 2.5v) + 7.3125 = 13.25 : 1 AFR. Assuming scale was 1-5v that puts mid @ 3v. Now put that into the equation and it
comes out to 14.4375:1 - close but no cigar. It would seem that you must, a) know the voltage output range used and b) the scale range used
as without these drawing any line or conclusion maybe way off.
This is Aem Aem instruction manual
Attachments
20221206_145316.jpg
Peter15
Posts: 19
Joined: Sat Nov 26, 2022 3:56 pm
ECU Model: P8 Pro
Distributor: Ebay
Firmware Version: V35

Re: P8, ana3 and set lambda parameters

Post by Peter15 »

katana wrote: Tue Dec 06, 2022 8:09 am
Peter15 wrote: Mon Dec 05, 2022 4:51 pm I found the formula:
Afr=(2,3750× volts)+7,3125
Lambda=(0,1621×volts)+0,4990
now it's easy
I'm assuming that is particular to AEM only, as other kits using 0v - 5v can have ranges from, as low as, 7:1 to high as 30:1.

Just for giggles I used your formula to check petrol stochiometric point (14.7:1) assuming a 0-5v range and it being midway in the range -
so, (2.375 x 2.5v) + 7.3125 = 13.25 : 1 AFR. Assuming scale was 1-5v that puts mid @ 3v. Now put that into the equation and it
comes out to 14.4375:1 - close but no cigar. It would seem that you must, a) know the voltage output range used and b) the scale range used
as without these drawing any line or conclusion maybe way off.
Lambda 1 not is 3volts but 3.1 volts
Lambda= (0.1621x3.1)+0.4990=1.0051
Afr=(2.3750x3.1)+7.3125=14.675
The Aem formula is perfect
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: P8, ana3 and set lambda parameters

Post by stevieturbo »

you don't need to calculate anything really when it's there in front of you in a table.
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