[drfrink24]

I must not be understanding how the ECU works, or, something is documented wrong, but, many of my numbers for total ignition timing just aren't adding up...

I'm trying to figure out where my timing numbers are coming from. First off, my IAM was 1.0 in all cases. From what I understand, that means the ECU will add the total ignition from either A, B or C dynamic tables, to the primary ignition table.

Here are some examples of my timing, including a calculated (excel) column that takes Total timing minus dynamic advance to yeild what I think should be primary timing:

 
Primary Load	RPM	DA	Total Timing
24	1.17	2117	5	29
21.5	1.25	2200	6	27.5
20	1.32	2251	5.5	25.5
20	1.38	2352	4.5	24.5
19.5	1.44	2439	4	23.5
19.5	1.44	2439	4	23.5
18.5	1.52	2545	4	22.5
17.5	1.6	2653	4.5	22
16	1.69	2750	4.5	20.5
14	1.81	2842	4.5	18.5
12	1.98	2982	5	17
12	1.98	2982	5	17
10.5	2.19	3107	4	14.5
8.5	2.46	3210	4	12.5
8	2.7	3361	4	12
8.5	2.79	3553	3.5	12
9	2.79	3708	5.5	14.5
9	2.79	3708	5.5	14.5
9.5	2.78	3934	9.5	19
11.5	2.73	4116	10.5	22
11.5	2.71	4280	10.5	22
12	2.71	4451	10	22
12	2.74	4594	10.5	22.5
13	2.72	4758	10.5	23.5
13	2.72	4758	10.5	23.5
13	2.72	4954	10.5	23.5
13.5	2.72	5114	10.5	24
13.5	2.68	5246	10.5	24
13.5	2.63	5399	10	23.5
14	2.57	5589	9.5	23.5
14	2.57	5589	9.5	23.5
14.5	2.5	5705	9	23.5
15	2.46	5886	9	24
15.5	2.42	6014	9	24.5
16.5	2.36	6147	8.5	25
18	2.32	6265	8.5	26.5
18	2.32	6265	8.5	26.5
20.5	2.27	6396	7	27.5
22	2.23	6506	6.5	28.5
23	2.21	6543	5.5	28.5
25	2.16	6650	4	29
27	2.13	6761	3	30
27	2.13	6761	3	30
27.5	2.01	6935	3	30.5
24	0.15	6544	0	24
24	0.15	6191	0	24
24	0.17	5876	0	24
24	0.17	5550	0	24

So, here is what doesn't make any sense to me. Even with extrapolated values, in many of those cases, my calculated primary timing is nowhere to be found (not even close to a value) in the actual primary timing map.

Its like there is a mysterious "actual primary timing map".

[WolfPlayer]

I think you need to search a little bit. I've been through this several times at this point. There is no way that you can calculate your total ignition timing so long as you are running a stock-type ignition map that uses the dynamic tables. You cannot add your primary ignition to some value that you get from the A/B/C tables. It just doesn't work that way. Check out my post from June where I tried to figure these tables out ...

Determining how the Knock Correction Maps Work

Moral of the story? Don't assume that you can calculate what your timing should be. The word 'dynamic' goes totally against that. The ECU starts with the base number in the primary ignition map but then adds OR subtracts OR (adds AND subtracts) from that number. What does it add or subtract? Ahahahahah. If you get that figured out then let me know. HOWEVER, I do have a theory that I am currently testing and will report back later on my findings. But, you're still stuck with the harsh reality of fact that you cannot calculate your timing based on the data in those tables. Why? Because the timing addition/subtraction is dynamic. Yes, it does start with main ignition, but the learning routines will modify that value. Furthermore, these values are also modified based on learned knock events / knock threshholds.

Wanna do a quick test? Reset your ECU, quickly get the IAM to 1.0 using a low-boost 5th gear pull. Now do 3 WOT runs. Observe your data. This is the start of learning how these tables sort of work.

I am hoping that my new thoughts prove to be true. If they are, then things are going to be cool ... really cool.

t

[drfrink24]

Wolf,

I must apologize. I wasn't understanding how this works. I was under the impression that determining when and to what extent the ECU pulls from tables A, B and C was the confusion, not the yielded total timing numbers. It also didn't help that some of the first logs I looked at actually did jive with primary + dynamic A/B/C.

[WRX_XB9R]

Wolf-
I have read all of yours and Christians posts on this subject. Thanks for all the info.

What size of DAM number are you looking for? I have most of my ignition coming thru at 3-5 now that I have played with the primary map a bit. This seems to keep me from getting knock. When the DAM is 7-10 it will get knock every bit and then I get massive losses in DAM sometimes even negative.

[WolfPlayer]

WRX_XB9R,

I don't think you mean DAM. DAM = Dynamic Advance Multiplier. This is the value that starts off at 0.5 after a reset and gets pushed to 1.0 so that the ECU can use all of the dynamic advance it wants. I think you mean just Dynamic Advance? I have seen Dynamic Advance values ranging across the board ... anywhere from 0 to 9 degrees of addition during WOT. When the car is running really stout I see values from 6-9. Normal is around 4-6. Bad is lower.

t

[WolfPlayer]

Originally Posted by drfrink24

Wolf,

I must apologize. I wasn't understanding how this works. I was under the impression that determining when and to what extent the ECU pulls from tables A, B and C was the confusion, not the yielded total timing numbers. It also didn't help that some of the first logs I looked at actually did jive with primary + dynamic A/B/C.

What you might find is that after a reset .... which means minimal learning time ... the total advance seems to be close to primary + A (on the first WOT run after getting the DAM to 1.0). If everything is good then more dyn. adv. may get added.

t

[WRX_XB9R]

I did mean DA Dynamic Advance.

Now have you tweaked your ignition maps at all? I used your rescaled baseline for 04 as my base. I have slowly increased some of the areas and decreased others till I am getting a smooth set of DA numbers.

[WolfPlayer]

Originally Posted by WRX_XB9R

I did mean DA Dynamic Advance.

Now have you tweaked your ignition maps at all? I used your rescaled baseline for 04 as my base. I have slowly increased some of the areas and decreased others till I am getting a smooth set of DA numbers.

I had tweaked things on a previous calibration but started over from scratch because I wanted to try tuning fuel before ignition. I am in the process of tweaking all the ignition curves again and just put a new map in this morning. I still hate shooting in the dark ... I'd really like to get that TXS knock monitor. However, since I am still using all the built in DA structure (not the values), I have fooled myself into thinking that I am still a little safe ... lol. I'll post whenever I get some concrete results. This might take a little while given that my life is basically dictated by my wife and kids rofl.

t

[drfrink24]

Wolf,

Just to clarify, you have made Dynamic Advance tables A, B and C all the same, correct?

[WolfPlayer]

Originally Posted by drfrink24

Wolf,

Just to clarify, you have made Dynamic Advance tables A, B and C all the same, correct?

To clarify ... NOT this time

I have tuned the timing several different ways. I have used Trey's special map that uses ONLY the 'A' table. I have also set all 3 tables equal. These appear to have the same effect; namely, they produce a DA curve that is predictable. These are really nice ways that work. They convert the STI to function like a WRX .... where there is only one DA table.

My new strategy is to tune these tables as Subaru designed them. This means that you have to know sorta how they work. A lightbulb went off the other night when I was staring at these tables ... and then bam I had to try this new idea that I had. If it works ... or if it doesn't ... I will post about it. But, I don't want to say what I am doing yet until I try it (because I don't want other to try it unless it is safe).

So, to recap - NO, I am not running static DA tables right now. They are different.

t

[drfrink24]

Well, if your idea proves correct, you'll go down in subaru tuning folklore...

[WolfPlayer]

Originally Posted by nhluhr

Wolf, did you ever have any luck figuring out your A,B,C DA tables?

Nick,

The most I have figured out is the following ...

1) Dynamic Advance seems to start with DA A. This is the safe amount the ECU will use on a reset if the DAM is 1.0.
2) If conditions are good it can rise to the amount in DA B (if the DAM is 1.0). Compare the stock DA A and DA B. You will see that they are identical except in the area that needs more protection (mid-to-high RPM at mid-to-high load).
3) DA C = I have no clue.

t