VN Tunerpro Help

[seabreeze]

It's always felt random being asked to save the adx. Good to know it doesn't muck anything up. I'm pretty sure i always save though.

Maybe i've inadvertently discovered a ghost cam tune?! Could be fun for a bit, but the motor is so smooth everywhere else it would be nice to dial this out.

[antus]

The thing is I cant see any signal on the inputs (havnt tried them all, tried the ones I thought it might be) that show a similar wave that the computer might be trying to counter for. Even the bubble traceing does not give clues. I thought it might be two wildly different cells next to each other and the bubble would be on the middle and leaning one way or the other, but all the cells are short of the max spark. So I am not sure what it causing it to go to so much advance. It must be one of the drivability things that is not working well with that cam. I also thought maybe it was the idle spark control, but confirmed in the data view that it is not in idle mode. At this point you probably need someone more familiar with tuneing big cams to offer their advice. If you cant get that advice you might be best going back to stock setting the temperature above to enable knock control to max to disable knock control (I see you changed lots of different settings and got the result somehow), and then put the spark, VE, injector parts in, maybe do the force open loop again if you need to, to stop the surging at idle and see how you go with less of the other changes. Or take a look at some of the other tunes for cams in the custom tunes area and see if there is a different approach taken in some of those.

You'll have to get the right ADX, I dont think these are 12P but you might be able to learn something. viewtopic.php?p=9771#p9771
Or the ones here are 12P, but be careful about version some of them might be older versions needing an older XDF. viewtopic.php?t=375 but to be a bit newer I'd take a look at wade's contribution here: viewtopic.php?p=70674#p70674

When I am doing it the save adx is usually because I am using the monitors and i've added an existing pid to one of the monitors. The save includes the layout and view of the monitors. I usually pick yes because I've set a monitor up for what I was last doing and want to pick up there again.

[antus]

I've had your log open on my screen for a while now and keep going back to it between other tasks. I havn't found a root cause. But my thinking is spark is above what is in the spark table, and VE is alternating up and down by a couple of % inline with the spark changes. So I think it must be one of the spark adders or removers that is toggling just above and below its threshold. I've been through the scalers that might be setting such a level, nothing jumped out to me as "this is likely the one". I've been through RDSC, Tip-In, ETC, ETC, but the cause and the solution has to be there somewhere.

[seabreeze]

I don't think i'm asking for less than 20 or more than 40 degrees timing in any table?! Maybe because i've played with so many settings, something in there is conflicting?

I went for a spin after work and found i could make it see-saw spark for hundreds of metres if i just blip the throttle then coast. As soon as i open the throttle a couple percent and keep it held, or come to a complete stop, the see-sawing stops.

This was all at low speeds. Couldn't make it happen by coasting on the freeway at 100.

Every other driving condition feels tight, responsive and controlled. Love driving this thing.

Even if i could squish the oscillations 5 deg either way it would feel so much better. It happens under decel so no load and can't hurt anything i'm guessing? ECM is probably working hard though.

I think your idea of going back to a fresh tune, with the important tables copied over, is the go. Found this good advice:

I am happy to add sections to the document with things that people might require like the rev limiter stuff, but honestly most of the other stuff 99% of the time you don't need to touch anyways and that is mainly why its not covered very much anywhere.

a lot of people tend to over complicate tuning, for example, I tuned a V6 sprintcar, which is basically a commodore v6 in a sprintcar chassis, so its got throttle body on the top of the manifold, whatever exhaust they like and they run them on methanol with bigger injectors to suit, but they are pretty much a stock motor other than that. The tables I needed to touch for that were:

* injector rate constant
* ve table
* idle and main spark tables
* injector battery offset
* first and second stage cranking BPW tables

that is all I needed to touch, other than things like fan on temp and idle speed but these are normal for anyone really.

the point I'm trying to make is a lot of the time you don't need to touch the other stuff and in doing so it only complicates things!

note: I didn't mention that I changed all the AFR tables from petrol to methanol numbers because this is out of the realm of normal tuning for most people and if you don't understand it I don't even recommend going there

Not knowing the cause is as frustrating as the symptom!

Appreciate the detective work.

[seabreeze]

Had a chance to play with this the last few nights and seems i have it fixed.

Fresh BLCF bin with VE, AFRs, idle P/N and Drive, crank BPW, and the few calibration specs copied over.

Had one stall coming out of the driveway, but once warm it was fine.

Looking at the log it seems there is a bit of see-saw spark, but it's barely noticeable while driving, and i couldn't initiate it like previous tunes.

One other positive it that it felt much more lively down low. Very happy with that.

I had altered a heap of parameters so hard to tell which exactly were causing my problem. Maybe stall saver? I would have to add each of my changes back in one by one and log to really find out...

Moral of the story is do just that! Change one thing at a time then log to assess results.

I'll probably forever be tweaking VE, but will turn on lean cruise and call it done for now.

Log and bin attached.