Well I too will say I enjoyed this, and I learned something, that being how the FP3 sets the fuel table:But I would be remiss if I didn’t point something out …
I believe you meant the FP3 map gives you a fuel table in Stoich (ie the Stoichiometric Ratio) and not in Lambda.
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As a follow-up:

What does the ECM actually use, Stoich or Lambda?

Is it dependent on specific years or applications?

Does the FP3 only use Stoich values and convert them when writing to the ECM?

Can the tables be changed as to which the ECM reads with a tuning device or are the ECM tables independent of the tuning device?
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Hi R how's tricks? no more lifter problems I hope? and that you had a good riding season. Mine has just headed off for the Scottish winter

I think it depends on the particular configuration. Same with whether the VE tables are MAP or TPS. Where some configurations allow either or MAP or TPS for the VE tables, I never noticed that you could change how the fuel table works ...but you can change how it is displayed in the Power Vision software (and set the stoich conversion value for the fuel you are using) so that you can swop the display between Lambda or AFR, depending on what you are maybe more used to.

The FP3 just seems to show AFR and I think if it is a lambda table (like the tourers) they always seem to use 14.7 as the conversion factor ...which isn't what most fuel actually is.

The configuration is what it is, the various tuners just read whatever is in the table, and then show what they need to/want to (I think ?!?)

And hrdtail78 will maybe jump in and beat me about the head with a big stick if I remembered that wrong

 

Gordon. I certainly did not mean to come off picking on you. Was not my intent.

The ECM deals in voltage. Oxygen sensors put out voltage. The ECM doesn't deal with lambda or ratios. Per-say. It doesn't need to. If you target 14.68, a lambda of 1 for any cell. When the ECM looks up that cell. It will see 450mV. 450mV is going to be used as the switching point. Any voltage output from the sensors, read by the ECM that is higher is rich. Any voltage output lower is lean. How this is controlled us by the ECM switching from two different modes. Rich mode and lean mode. While in rich mode. The ECM will shave milliseconds off injector time until the ECM's mode switches to lean. Then the ECM adds injector open time and it goes to rich mode. So, basically it wobbles the lambda, ratio or voltage. The VE table represents air flow through the engine. It is a starting point that is used to where this wobble of the injectors need to take place. How much this starting point biases rich or lean is correct by trims. These trims are either applied as short term or long term. If the short term trim takes a big enough hit in correction. The long term takes the hit and centers the short term. Recording these trims and applying them to the calibration that they were collected with in a program. Applies the trims permanently to the VE tables in a new calibration.

 

Hells bells no worries on that score pal, I didn't think you were
I was just joking around meaning that you'd keep me right if I had forgotten all the stuff that you and a few others had taught me over the years. Some of us do try to listen but older age n what not, some of us also start to forget ...and need a prod or two from time to time if necessary

As usual, all good helpful stuff, cheers pal.

 

Gordon, bike great, weather this season sucked! Planing on a ride tomorrow.

I could be wrong, but I believe the AFR tables and VE table choices are separate issues.

From what I understand (and hrdtail78 kind of confirmed) the ECMs and maps that use closed loop would store the AFR table using lambda; using the lambda value itself, or a corresponding voltage which the ECM will actually use. (If I were coding it, I would do the former and have a hard-coded table to convert the lambda value to voltages.)

Which means the FP3 is converting those values to stoich when it displays the table.
No harm, no foul, it doesn’t really mater if you realize it is only based on a single fuel.
The FP3 would still be writing a lambda value to the ECM, so the fuel wouldn’t mater.
(Though not being able to change those values is less then optimal to me.)

The PV (using the WinPV software) will display the AFR table in either, and when showing in stoich can change the value based on the fuel used (not needed with lambda values.)

I believe this is a throwback to when there was only open loop.
Not really needed unless one is tuning a bike in strictly open loop, on a system that would be reading stoich values.

Which goes back to my questions (now slightly modified):
Do the ECMs and their tunes that are strictly open loop store the AFR values in stoich, or do they still use a form of lambda?
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