wideband logging

[steveo]

damn i wish i was better with disassembly. i'll look for it, though. i've found some misc. parameters before but this might be a bit out of my realm.

either that or im going to owe robert a whole ton of beer...

[EagleMark]

damn i wish i was better with disassembly. i'll look for it, though. i've found some misc. parameters before but this might be a bit out of my realm.

either that or im going to owe robert a whole ton of beer...

You and every other LT1 owner already owe him a ton of beer! Don't know if you did so but a message of thanks to him in your XDF or writeup would be in order.He's very modest and overlooked at all the work he has done for the DIY Tuning community! I'd bet he already found it on the V6... if you had that address or algorythm it would be a good place to start looking with TP 2d tools and use his Parameter. Then test... does LT1 show commanded AFR in data? Like when entering PE...

[steveo]

no, i'm almost certain it does not have any datastream value for commanded AFR, i've been all over every byte of that damn datastream in my datalogger project.

as far as credits go, i do have an edited note of thanks as follows in my current xdf header (not uploaded yet, still finishing a few other changes up):

Special thanks to:
robertisaar for his amazing disassembly work finding the new o2 parameters, the gearhead-efi.com crew for their major contributions to this project, and to Mark from Tunerpro for his foundational work in the EE platform.

it's very hard to pay back peoples help into useful compensation other than the odd thank-you.

i know this very well, i also contribute many hundreds of hours online helping people with their car problems without recieving even a thank you most of the time. but, you know, if you dont enjoy doing it, then dont do it.

as far as my fbodytech site goes, nah, no credits. there are too many sources. i dont even give myself credit :P

[EagleMark]

Again, if found in dissasembly it can be swapped in place os something else. But not really needed as you could find the Stoich by testing with WB.

[steveo]

you know what, i think i've tuned my way around having that value available to a certain point, if i had it available, im not sure i'd even change it... but wow would it be awesome to have in my xdf.

i think when im done wideband tuning my PE mode stuff (when the roads dry out) i'll dig a bit more into it and see if i can get it. i need the practice.

[RobertISaar]

follow the BPW calc far enough back and it will most certainly be involved..... may be faster to find working forward though, since the airflow calculations are pretty well understood. once airflow is calculated, the ratio of fuel to mix with the air shouldn't be too far after.

[steveo]

makes sense, i'll try!

i'd expect a fairly obvious branch somewhere, where it either does a lookup on the open loop fueling table, or based on (this variable), then scales it with all the closed loop stuff, right? i assume it'd check the closed loop enable bit itself as its sole condition

i think i can chase it based on those assumptions.

[EagleMark]

follow the BPW calc far enough back and it will most certainly be involved.....

Yup... From other masks it is the first thing used in BPW calculation. I believe both injector flow and displacement has been found in $EE, so reversing should find one more number in the calculation.

The value 1461.5 below is the Stoich AFR, where PFI uses 365.375 which is 1/4 of the TBI setting, I'd guess this is to do with firing of injectors per cycle difference.

 TBI 
					;   Val = 1461.5  * (VOL/RATE)
					;           VOL  = Vol of 1 Cylinder in liters, (0.7125l)
					;           RATE = Injector flow in gms/sec
					; 				   5.7l = 7.71 gms/sec (61.2#/HR)
					;				   (VOL/RATE) = 0.0924	l/gm/sec
PFI 
					;    Val = 365.375 * (VOL/RATE)
					;           VOL  = Vol of 1 Cylinder in liters, (0.7125l)
					;           RATE = Injector flow in gms/sec
					; 				   5.7l = 1.92751 gms/sec (#/HR)
					;				   (VOL/RATE) = 0.3696 l/gm/sec