Can you post your map?

 

I'm not talking about that authority range. I'm talking about the meaning or interpretation of the CAS signal. That's really what he's asking. 118 in Xmap corresponds to -10 in pyxede. I am under the impression that this is 10 degrees off TDC, but maybe it means something else.

EDIT: this conversion factor can't be a factor of any xede setting because that would because it would conflict with the ECU software. Either way, I feel a little underqualified to make meaningful contributions to the discussion, so I'll withdraw myself.

d

 

I've posted enough of my log to show that if that number -128 is timing then I am running negative timing almost all the time. I tossed in a formula to show how negative it is in the last post.

Timing normally builds from the time you get on it to the time you hit redline.....unless its maxed out or you run into knock. Normally a person can add more timing up top as well.

I dont understand why my timing would SMOOTHLY get less and less as RPM's climb.

6523 120 -8
6545 120 -8
6559 120 -8
6588 120 -8
6595 120 -8
6604 119 -9
6620 119 -9
6620 119 -9
6641 119 -9
6646 119 -9
6655 119 -9
6655 119 -9
6655 119 -9
6663 119 -9
6671 119 -9
6671 119 -9
6690 119 -9
6723 118 -10
6734 118 -10
6750 118 -10
6753 118 -10
6776 118 -10
6792 118 -10
6792 118 -10
6804 118 -10
6830 118 -10
6830 118 -10
6850 118 -10
6857 118 -10
6857 118 -10
6877 118 -10
6877 118 -10
6884 118 -10
6884 118 -10
6903 118 -10
6918 118 -10
6939 118 -10
6958 118 -10
6958 118 -10
6974 118 -10
6984 118 -10
6995 118 -10
7024 118 -10
7024 118 -10
7045 118 -10
7053 118 -10
7053 118 -10
7056 118 -10
7074 118 -10
7074 118 -10
7096 118 -10
7121 118 -10
7121 118 -10

 

Since we're dealing with 8-bit signals, I don't think that a map that made a change of 0.1deg would do anything if 118 = -10deg.

Also, if 118 = -10deg, then 0 = -128deg ?? What would be the point?

We need to log the Xede's output with differently scaled timing maps loaded in... For example: two maps, both running -1deg... one scaled at +/-10 and the other at +/-5 (EDIT: obviously, we can't do this on a SMART car... it's gotta be V2 or V3).

Is it logging the Timing map + Smart timing ? ... or just Timing map?

 

Oh man don't get me started on the timing adjustments in the XEDE.... timing adjustments of .3 to .9 are a joke....thats why I wanted to know if that value actually ment .9% of overall timing not .9 degrees.

So that being said I still haven't gotten an answer that makes sense.

 

Because the value you see is the number of units (probably degrees) before top dead center. -10 is 10 degrees before TDC, so 10 degrees advanced. The advance is postive, but the signal modification is negative?

Ok. I'm really done now. Resume arguing.


d

 

No, no, no. The datalogging is at 8bit precision, but the internal ADC and DAC is at 10bit. So you really do get 1024 values and one digit after the decimal.


No, no, no...again. It's logging the crank angle signal. All you see is the final result after ALL modifications are done to it. Ok, I'm really done now.

d

 

OK, but I still don't think 118 = -10deg. The logging must be "finer" than that!

I'm saying the things I am based on what I have seen in logs from my own car (non-SMART). I'll experiment and post logs later if I get the chance.


It's logging the *change* to the CAS, not the CAS itself. The amount of change in the CAS signal is determined by the timing maps.

 

At first I thought that too....but you know when you get off WOT and coast down.....timing should actually advance and say at the max advance value.....this doesn't happen. (Changed the value to represent adv in timing)


5565 118 10
5583 118 10
5583 118 10
5592 118 10
5602 118 10
5620 118 9
5628 119 9
5639 119 10
5647 118 10 Getting off throttle here
5641 118 10
5626 118 8
5626 120 5
5581 123 4
5581 124 6
5517 122 8
5517 120 5
5462 123 9
5437 119 6
5437 122 3

 

You're saying the Xede should advance your timing?? Only if you're using Shiv's absolute latest SMART map.

From the looks of it, either your motor is noisy (SMART retarded timing) or you have negative values in your timing map under low load. The Xede cannot report actual ignition timing because it doesn't get the ignition signal (it would need CAS and Ign to calulate actual timing).

Again, can you post your map?

 

I am not using SMART.

Timing should be getting advanced by the ECU when at partial throttle, no load, or when no knock is detected.....thats how the ECU works.

I have no idea WTF the number in commslog means because it certainly doesn't represent overall timing or timing advance for that matter.

My map isn't gonna do you any good.....its a hybrid between Stage 0+ and Stage 1. All negative timing values on the timing charts....but all of them are between -.3 and -1.1 either way these values mean jack **** when considering the overall timing the motor sees. Negative .3 degrees is next to nothing.

In the attached graph you can see how the ECU controls timing vs boost, throttle, and RPM.....timing is maxed out at partial throttle.....then when you hammer on it it drops down and start to climb....when you get off throttle it maxs out again.

 

This is what I've been saying all along... the number in the commslog is NOT ignition timing. It is the Xede's offset to the CAS signal, as determined by the Xede's timing map(s).

...and -1.1 to -.3 corresponds *exactly* to the CAS offsets you are seeing in your commslogs.

Again, if that graph is from the Xede, it is NOT actual ignition timing.

 

That graph is from a DSMLink in an EVO.

Unless you know of a way to actually read ignition timing from the ECU then I guess I am out of luck.....looks like I'm just gonna go get a pocket logger.

 

I just made some test logs...

With the timing map scaled to +/- 10deg, I set the timing offset in the idle area of the map to +1.0deg. CommsLog gave me a value of 138.

Next, I set the timing offset to -1.0deg, and CommsLog showed 117.

Both of these correspond to a scale where 0 = -12.8deg CAS offset, 128 = 0deg, and 255 = +12.7 deg.
(very much like the scale we see in the SMART timing map)
I think the 117 = -1.1 in the table is *possibly* from a rounding error, similar to the rounding I mentioned in my previous map-editing example exercise.

Try it out yourself with different values and draw your own conclusions.

 

Ahh.. I was thinking it might be from donour's Xede logging/graphing program.

Yeah, you're gonna need something else, 'cause the Xede is unaware of actual ignition timing.