LBZ equivalent of B0751/B0752?

[bballer182]

Killerbee, Yes they can be, if I recall the maths allows it to go from -32 to 32 (it's a signed value).
What do you need, 4 or 5? I just like to keep things sensible for other users, putting in 32 would be ridiculous.

Cheers,
Ross

I was wondering the same thing. 2.0 lambda = .5 EQ

So 4.0 lambda = .25 EQ

I can't possible see anyone tuning below that. It would be completely pointless to do so. And correct be if i'm wrong but there is no possible way to tune for negative lambda so zero would be the minimum. And even zero would produce a "divide by zero error" wouldn't it? So something like .001 should be the minimum, right?

[GMPX]

I know, minus Lambda seems odd, but they are signed numbers.
Probably more like 0.5 should be the minimum. Div by zero, the famous ECM killer, they may have a trap for that, I'm not sure.
I'm happy to put the limits at whatever, but I just try to keep in mind that someone might have a play and set it to something very silly just to see what happens. Granted unlike a gasser where allowing people to enter in 60 degrees of timing would be fatal, probably this is not so bad for the Diesel.
I'll just keep an eye on the discussion and decide from there.
It is however good news that it appears to do something positive.

Cheers,
Ross

[killerbee]

So 4.0 lambda = .25 EQ

It's not working that way. I use 2.0 and can get 1.1 EQ (calc_pid). My pulse and pressure tables may be why this is happening. Lambda could be based on assumptions we are not able to determine.


Ross, I think 4 would be enough.

[JoshH]

It's not working that way. I use 2.0 and can get 1.1 EQ (calc_pid). My pulse and pressure tables may be why this is happening. Lambda could be based on assumptions we are not able to determine.


Ross, I think 4 would be enough.

Your EQ pid will be all but useless for tuning with the lambda. What have you changed that is making it smoke so much? I've never had an LBZ or LMM that had smoke problems unless they had enlarged injectors. Did you add a bunch of PW to the lower fuel quantities or something?

[killerbee]

It would be easier to describe what has not changed.

It is a ground level-up project.

FWIW, the pressure table has no resemblance to stock, as an example.

[bballer182]

It's not working that way. I use 2.0 and can get 1.1 EQ (calc_pid). My pulse and pressure tables may be why this is happening. Lambda could be based on assumptions we are not able to determine.


Ross, I think 4 would be enough.

Correct, I too believe that the lambda table is based on stock tune assumptions, much like the DIC mpg calculation.

[bballer182]

Your EQ pid will be all but useless for tuning with the lambda. What have you changed that is making it smoke so much? I've never had an LBZ or LMM that had smoke problems unless they had enlarged injectors. Did you add a bunch of PW to the lower fuel quantities or something?

Calc_pid or not you can look at the tail pipe and tell it's obviously over .9 EQ... Anything over .9 EQ (actual, not calculated) will be smoky.

[bballer182]

I know, minus Lambda seems odd, but they are signed numbers.
Probably more like 0.5 should be the minimum. Div by zero, the famous ECM killer, they may have a trap for that, I'm not sure.
I'm happy to put the limits at whatever, but I just try to keep in mind that someone might have a play and set it to something very silly just to see what happens. Granted unlike a gasser where allowing people to enter in 60 degrees of timing would be fatal, probably this is not so bad for the Diesel.
I'll just keep an eye on the discussion and decide from there.
It is however good news that it appears to do something positive.

Cheers,
Ross

Yeah that sounds good. I think it might even be pretty close to impossible to fuel to a 2.0EQ unless there is a huge replacement non-VGT single turbo in the works.

[JoshH]

It would be easier to describe what has not changed.

It is a ground level-up project.

FWIW, the pressure table has no resemblance to stock, as an example.

I don't think the pressure table will create excess smoke unless you are dropping a significant amount of rail pressure causing the fuel not to atomize correctly. The only thing I can think of that would cause large amounts of smoke at tip in would be if you made significant increases to the pulse width in the fuel quantity range of 50 mm3 and below or if you have larger injectors installed. Perhaps I'm way off, but that's my thinking regardless. I'll just say this, I never touch pulse widths at 50 mm3 and below, and I never have smoking problems on stock injector LBZ and LMM trucks.

Calc_pid or not you can look at the tail pipe and tell it's obviously over .9 EQ... Anything over .9 EQ (actual, not calculated) will be smoky.

I realize that, but the ECM can't see the smoke. It only goes off of what it thinks is the fuel quantity it is getting and the air quantity it is getting. If you fool the computer so that the fuel quantity it is using is actually more than what it thinks, your lambda values will be off. On the flip side, if you make it think it is getting less air, by rescaling the MAF sensor or putting a larger diameter intake pipe on, your values will skew back the other direction and vice versa. That is what I had been experimenting with before this table was released, but it is quite sensitive and much harder to get dialed in properly I believe because there was a lack of RPM control. I was trying to avoid playing with the pulse width table because I didn't want to affect the shift defuels at part throttle.

[killerbee]

much like the DIC mpg calculation.

that's what came to mind for me also as I try to evaluate.