New Tuning Tutorial: WeathermanShawn

[WeathermanShawn]

I noticed the calc pid in the tutorial and the one in shawn's first post are different. The LTFT BEN in the tutorial ends in...)/2/100+1 where as the attached file ends in /200+1. Also for the sake of clarity, should the attached calc pid in the post have "displacement" instead of the actual number(5.669). For newbs to EFI live, shouldnt we make it as easy to cut and paste as possible? Also, I noticed in the tutorial when showing how to do the filtering, the second screen shot shows temp in metric where as the first is imperial.

Good eye on the filter temps. Missed that one...

Let me look over the LTFTBEN..I think I know what you are referring too. I believe they are mathematically equivalent, but it could be a typo, so thanks.

Yes, the CALC.PID should read displacement. There has been a problem using displacement instead of the actual value, but I believe the latest software corrected it.

As far as 'cut and paste', believe me we saved a lot of steps with this method. A lot of the 'cut and paste' is being accomplished by the CALC.VE being multiplied instantly by the LTFTBEN, but I hear you. First couple of months I thought the same thing. Now, it is a distant memory.

I think that covers your last few points. Thanks for pointing out some problem areas.

As far as the wideband..If you can keep out of KR and avoid WOT, and trust your narrowbands..the method will work. But, I can not responsibly suggest it. Even today, a wideband saved me from some headaches. Your mind can fool you. Rich, lean are very hard to guess at. But, the method is not wideband dependent to work..your $6000.00 engine can go lean and start doing damage really quick. I think widebands should be mandatory in tuning..

[WeathermanShawn]

I've found the GM.AFR pid to be unreliable at times and gives a different value
to what {B3601} & {B3618} are.

Mr. P..off by a lot?

[TunasTwins]

I hope you understand I'm trying to make this method workable for the challenged(me) The formula looked correct to me so I was just pointing it out. I'll try and test this out as promised and will report back. TIA!

[WeathermanShawn]

No, I understand. We honestly appreciate the feedback...

[mr.prick]

I've found the GM.AFR pid to be unreliable at times and gives a different value
to what {B3601} & {B3618} are.

Mr. P..off by a lot?

Commanded AFR ≠ {B3601}

Not when EQ1 is commanded but when PE comes on it was returning
a leaner value than what commanded EQ was.
I feel that is unacceptable.

If commanded AFR is leaner than {B3618} then
BEN will pull out fuel when it should not.
{GM.EQUIVRATIO} is reliable and always matches {B3601} & {B3618}

[joecar]

I noticed the calc pid in the tutorial and the one in shawn's first post are different. The LTFT BEN in the tutorial ends in...)/2/100+1 where as the attached file ends in /200+1. Also for the sake of clarity, should the attached calc pid in the post have "displacement" instead of the actual number(5.669). For newbs to EFI live, shouldnt we make it as easy to cut and paste as possible? Also, I noticed in the tutorial when showing how to do the filtering, the second screen shot shows temp in metric where as the first is imperial.

Welcome to the forum...

Those two are the same.

displacement() doesn't seem to always produce a value.

Good point... depends on whether your calc_pids.txt already has stuff in it or not.

Good catch, thanks.

[joecar]

Commanded AFR ≠ {B3601}

Not when EQ1 is commanded but when PE comes on it was returning
a leaner value than what commanded EQ was.
I feel that is unacceptable.

If commanded AFR is leaner than {B3618} then
BEN will pull out fuel when it should not.
{GM.EQUIVRATIO} is reliable and always matches {B3601} & {B3618}

I have seen a few times where GM.AFR wasn't {B3601}/{GM.EQIVRATIO}... I'll have to dig thru my logs to find some examples...

[WeathermanShawn]

I notice you guys use EQ (always) instead of AFR. Am I behind the times here, or is that necessary if you are only working with one OP.

Any inherent advantage?

[joecar]

The advantage is that it allows you to instantly see the % richer/leaner (i.e. the fraction part).

Here's my current calc_pids.txt.

[mr.prick]

I use EQ for the reason I stated previously.
It gives you an accurate multiplier and you don't need to worry
about your WBO2's stoich AFR not matching {B3601} perfectly.
Using AFR is fine if both match closely and {GM.AFR} is what it should be.
You can change the analog output slope or expression to match {B3601}
but there is still the accuracy problem with {GM.AFR}.