using 14.047 for desired AFR and not 14.63?

Quote:

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Originally Posted by mr.prick

After you save the tune values will change slightly.
Example:
14.4AFR becomes 14.42AFR.

Don't forget to change the fuel settings in your WBO2 controller to match
your new EQ1/Lambda1 and any cal_pid formulas you have relating to EQ/Lambda.

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Correct. Stoich is always 1.0 for lambda/EQ no matter what the fuel (gasoline, E10, E85, etc.). AFR is what changes and why the WB controller needs reprogrammed.

What get's tricky is logging EQ...

It's not a linear output like the AFR voltage equations are. Further below in this thread, I explain further. With a little work in Excel, the equation can be discovered. With that in mind, it's also important to keep in mind what you really put in your tank so you can set B3601 accurately...

http://www.e85mustangs.com/regions123.html

Because they mix it up at the pumps. :)

That is what I was wondering. So you can not assume that the given 7.35 half of the WBO2 AFR is correct when using a fuel that has 10% ethanol as stioch and is the fuel we have mostly everywhere I live. So half of 10% ethanol (14.07 stioch) is the given (7.035 instead of 7.35) plus the reading from the sensor? I guess you cant do that in all reality, so you actually really do have to use EQ or lambda when tuning and logging? I an still not sure I am saying this right but the answers are sure helping me get my brain around this.
98 tigershark

I can't match Lambda1 to EQ1 exactly between the WBO2 settings and {B3601}.

Off topic
I just looked at an old log and found
GM.AFR differed ever so slightly than what is set in the tune.
Example:
----------{B3601} = 14.628573 AFR
Actual commanded = 14.627930 AFR
Difference-------- = 00.000643
When PE kicked in GM.AFR was slightly lean too.
Is there a multiplier somewhere?

I think GM uses the 7.35 for half of the PID calculation or close to it as an adjustment and has something to do with the EQ to Lambda thing, I dont really know but it seems that way. (you know the 7.36 or .5/ ADV1 or 2 thing were it says that bank one is 2.20 or approx before you change it to the WBO2). I still dont think I said that right. Anyway awhile back I read that the PCM simulates one of the banks and one is the actual as to Bank 1 sensor 1, bank 2 sensor 1. I will try to find the GM or EFILive article I read.
98 tigershark

Quote:

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Originally Posted by mr.prick

I can't match Lambda1 to EQ1 exactly between the WBO2 settings and {B3601}.

Off topic
I just looked at an old log and found
GM.AFR differed ever so slightly than what is set in the tune.
Example:
----------{B3601} = 14.628573 AFR
Actual commanded = 14.627930 AFR
Difference-------- = 00.000643
When PE kicked in GM.AFR was slightly lean too.
Is there a multiplier somewhere?

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Just to clarify {B3601} Our pulsewidth calculation by the PCM would be this.
IBPW=( Airmass/({B3601}/commanded EQ)/IFR) + offsets
Correct?????
Going by this an error in B3601 would still cause an error in our airflow model if we are commanding away from stoich like in a custom OS.

I thought the PCM knows to or uses (BSFC) the brake specific fuel consumptions change to adjust for nat asp or forced induction for the COS's and also the uses VE% too. Maybe just for WOT?
98 tigerhark

Quote:

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Originally Posted by 5.7ute

Just to clarify {B3601} Our pulsewidth calculation by the PCM would be this.
IBPW=( Airmass/({B3601}/commanded EQ)/IFR) + offsets
Correct?????
Going by this an error in B3601 would still cause an error in our airflow model if we are commanding away from stoich like in a custom OS.

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Quote:

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Originally Posted by 5.7ute

Just to clarify {B3601} Our pulsewidth calculation by the PCM would be this.
IBPW=( Airmass/({B3601}/commanded EQ)/IFR) + offsets
Correct?????
Going by this an error in B3601 would still cause an error in our airflow model if we are commanding away from stoich like in a custom OS.

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Are you saying IBPW will change commanded AFR?
Shouldn't commanded be static, other than after start, ECT,IAT multipliers?

Quote:

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Originally Posted by mr.prick

Are you saying IBPW will change commanded AFR?
Shouldn't commanded be static, other than after start, ECT,IAT multipliers?

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No, what I am saying is an error in B3601 will bring errors into AutoVE if commanding away from stoich.
An easy example would be like this.
lets say cylinder airmass is 0.62 G/cyl. commanded afr is 1.14 EQ and the IFR is 5.0 G/sec. Offsets we will leave at 0 for simplicity
B3601 set to 14.63

IBPW = 0.62/(14.63/1.14)/5.0
IBPW = 0.0096623 sec

B3601 set to 14.04

IBPW = 0.62/(14.04/1.14)/5.0
IBPW = 0.0100683 sec
A difference of 0.000406 sec or near 1/2 m/sec in commanded pulsewidth.
I havent fully worked this out yet & could be chasing shadows or just plain overcomplicating things. Time to fire up excel & do a little math.:doh2:

Thanks for doing the math 5.7ute. You should look at SSpdDmon link regarding E85. its pretty scary and means were I live we get the crap fuel year round. That really sucks!! But since we get the crap fuel all the time I guess it at least will be consistent for tuning so thats a positive. By the way since the AFR is set for 10% ethanol it would take a bigger pulse width as the fuel milage does also go down, Right! as it seems your math is right to me and it should be a longer IBPW.
Thanks again as I think this will be very important to learn as I sure am.
98 tigershark

Guys, I just don't understand the resistance to using either lambda or EQR. I know you've been conditioned to see gasoline AFRs all along, but it's time to move on. You're only causing yourselves more unnecessary headaches.