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Discussion Starter #21
Update: I wanted to point out something that I had mentioned above ... and tweak some of what I said previously.

I think the very first thing that somebody should do after feeling comfortable working around in the software is to rescale the tables with the proper load values due to how Cobb is supplying this Stage II ST map. So, given what I said above about boost->ignition->fuel (BIF, lol) ... I would recommend only doing this after you have rescaled the tables to the proper load values. Rescaling to at least 3.25 is recommended. This is kind of a catch 22 because nobody wants to do something major like rescaling the tables as a first mod. It is daunting and somewhat complicated. Thus, it's easy to start with BIF in order to gain confidence in what you are doing.

Long story short: We need a better starting point than the stock Cobb Stage II map. We need a Cobb Stage II map with appropriate load columns for the VF39.

t
 

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Why do you do BIF? Just curious as I have the inclincation to do it BFI followed by possibly a small tweak of F after the final I. So I guess I like BFIf. :)

It seems the ECU itself spends more time tweaking ignition as well, so it seems to me like that is the last part to adjust. Just my ignorant opinion of course.
 

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Discussion Starter #23
daemon,

You really will hear arguments either way. BFIf is a very fine approach. Nothing wrong there and you will never hear me talk bad about that approach. I have used it myself on multiple occasions. Why did I do BIF here? Simply put, I didn't want to play around with the timing after leaning the car out when I have never tuned an STI before. After verifying that I was rich I then went back and started playing with the timing ... in a safer environment that would be more forgiving if I made a mistake when playing with the timing. If you make a mistake in tuning the timing when the car has already been leaned out then ... kaboom.

t
 

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Kind of a tango between fuel and ignition. Just keeping honing in I guess. Since extra fuel slows down the flame front, you can add more timing. But then when you lean it out a little, you've changed optimal timing again and might need to retard a bit.

I guess one question is, is there a timing value regardless of AFR that produces the most power at that load (not equal power regardless of AFR, but best power possible given any AFR). That is if you run 10.8 AFR in the entire fuel map, find the best ignition curve, and then change the AFR to say 11.2 for the entire fuel map and find the best ignition curve, are those two ignition curves 100% identical? If yes, then that is the perfect argument for BIF. I have sort of assumed no, and so therefore BFIf seemed logical.
 

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Discussion Starter #25
daemon,

Your assumptions are correct. A timing value regardless of AFR? No way. Everything is so dependent on each other. Everything really needs to be done cyclically. No such thing as BIF or BFI. BFIf or BIFi? ... hahahah ... probably more like bfifififififif or bifififififififi (lol) because some of us are never done :)

Both are totally viable methods and it really depends on the tuner.

Leaning out the motor before going to more aggressive timing is safer (BFI)
Adding more aggressive timing on a richer motor is safer (BIF)
Adding more aggressive timing on a leaned out motor is sketchy (BFI)
Leaning out a motor with more aggressive timing is sketchy (BIF)

Pick your poison :)

t
 

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Welcome to the world of Dynamic Advance. Reset the ECU and do a couple WOT runs. Within 3 WOT runs your DA will have completely learned and you will be running max DA (which will most likely be higher than what you just logged)..........

......- After a reset the Dynamic Advance Multiplier (aka Ignition Advance Multiplier or IAM) is at 0.5. Simply putting the car in 5th gear at low RPMs and holding boost to 4-6 psi for a few seconds will max it at 1.0 very quickly. Neato Mosquito.
Hi Tim,

My Street Tuner package should arrive today ! My plan is to get some base data at the track with the off the shelf stage 2 93 maps then change to the ST.

One thing I noticed at the track is my first passes are always the quickest and fastest. Considering what I read in this post, I wonder if the problem is the Dynamic Advance. I would like your opinion about the best way to correct at the track. It seems like I can reset the ECU and do the fifth gear boogie you describe above (hold at 5~6 psi for a few seconds). Only concern is the affect on ECU ability to work up to target boost after reset..

What do you think ?

Thanks,
 

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My guess is that the heat is the reason you run slower after the first run. Either intake temps are climbing or the intercooler is getting heat soaked, or both. I'd log your IAT and ignition and see if there is a change between runs. You might also want to wet down your IC between runs.

BTW, there is a difference between dynamic advance and the dynamic advance multiplier. The multiplier is the one that trick works at increasing quickly. And, fwiw, if either of them dropped that quickly after a run, I personally wouldn't go tricking it back to max for the next run. It adjusts for a reason. If you find it adjusts unnecissarily, then fix the tune, don't go messing with the learning system itself.
 

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Discussion Starter #29
I reiiterate pretty much what these guys said. After a reset the DAM (IAM) goes back to 0.5. Also, as previously indicated, the actual Dynamic Advance also goes back to minimum.

After an ECU reset and bringing the DAM back to 1.0, it would take just about a full 1/4 mile run to relearn the appropriate ignition advance (my logs show 3 WOT runs of 2 gears so it may take a little more than one 1/4 mile run). The only way around this is to do what I did ... i.e. running a custom Base Map that uses all of the Dynamic Advance that you specify and doesn't vary it like the stock maps ... or to set all 3 dynamic advance maps (A,B,C) to the same values.

t
 

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I've been copy-pasting all of the maps into MS Excel so I can rescale them for a higher Load. The primary fuel map is cake. The 0.25, 0.4, and 0.55 load columns contain the same values, so you can just remove 0.4 and slide everything over without any negative impact on the map. The dynamic advance maps are also the same, but primary ignition looks like it will be tricky.

I'm rescaling the v1.10 stage 2 base map, I will post the map and results when I am done.
 

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Discussion Starter #31 (Edited)
jaygoesfast said:
I've been copy-pasting all of the maps into MS Excel so I can rescale them for a higher Load. The primary fuel map is cake. The 0.25, 0.4, and 0.55 load columns contain the same values, so you can just remove 0.4 and slide everything over without any negative impact on the map. The dynamic advance maps are also the same, but primary ignition looks like it will be tricky.

I'm rescaling the v1.10 stage 2 base map, I will post the map and results when I am done.
Hahahha, too funny. I just finished completely rescaling a Cobb 1.10 Stage 2 Map. Here is a pic of the primary fuel so that you can see what load factors I used. Since I can hit about 3.1 on a stock Cobb map I have a 3.10 load column. Also, for safety I have one column higher than 3.10 to cover situations that will go beyond 3.10 unpredictably (boost creep, maybe a really cold day, maybe way below sea level, etc). IMHO, you should have one protection column preceded by a column having a load value that equals to or is slightly larger than your normal max load.



I have this base map completely done with everything converted (fuel, ignition, all dynamic advance maps, etc) and the correct LINEAR INTERPOLATION done. Check my post on Cobb's General streettuner forum about linear interpolation .... hmmm ... maybe I'll crosspost it here ...

http://www.wrxforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=12;t=000222

NOTES:
1) I may decide to decrease the LAST column to 3.25. Depends on some more research that I am doing. EDIT: I actually rescaled it to 3.30.
2) This is a STOCK map with rescaling and linear interpolation. Nothing has been tuned on my part. Again, stock Cobb values or interpolated values using real linear interpolation and not Cobb's interpolation.
3) For right now 2.8, 3.1, and 3.4 contain the same values as the original 2.75 load column.

t
 

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Haha, mine is done now too with the exception of ignition timing, I think I will leave that one alone and build some extra safety into the dynamic advance maps.

I might even try it tonight, I was going to flash the v1.10 base anyways to get the new closed loop delay settings.
 

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Holy cow. I had assumed the interpolation was done they way you describe it should be as opposed to the way you say they are doing it. I guess I should have done a few calculations of my own before making those assumptions. Darn assumptions. Always causing problems.
 

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WolfPlayer said:
I have this base map completely done with everything converted (fuel, ignition, all dynamic advance maps, etc) and the correct LINEAR INTERPOLATION done.

Hi Tim,

What do you think about sharing the improved base map? My ST delivery was delayed
but I expect it tomorrow.. I would like to start with your map instead of the "stock" one... what do u think???
 

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daemon said:
And, fwiw, if either of them dropped that quickly after a run, I personally wouldn't go tricking it back to max for the next run. It adjusts for a reason. If you find it adjusts unnecissarily, then fix the tune, don't go messing with the learning system itself.
Good points... thanks
 

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I got my new rescaled map running on the car tonight. Everything seems normal. It's odd though, I thought the only way you could rescale was by flashing the base map. I flashed the new map as the base map with my AP and it did not update any of the tables that I had rescaled. I had to load up ST, go into live tuning, and load the base map from ST to get it to stick.
 

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Discussion Starter #37 (Edited)
Jay,

Let's carry this conversation over to a new thread I just created :)

I mentioned this problem ... umm feature ... in a previous thread. Flashing a base map does not overwrite any realtime info. If you want a complete reflash you need to flash the basemap and then upload a realtime version of the basemap you just flashed.

Cool deal on the rescaling working for you. BTW, did you rescale a STOCK Cobb Stage 2 map or did you rescale your modified map? I'm thinking of putting together a website where we can upload and download our maps (along with a description). Who knows ... maybe I'll get this done today and we can put our maps out there for others.

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WolfPlayer said:
The values I have seen others use for TOTAL IGNITION TIMING are 18 at 4000rpms, 22 at 5000rpms, 24 at 6000, and 28 at 6800.

Wolf,

Quick question.. I'm looking at some logging from a few weeks ago (low humidity, 55 degrees) and I'm seeing 20/22/24/30 (varys). This is the v1.04 stage2 basemap, of course, 100% throttle.

Are the values you recommend starting points, or, ending? I find it hard to beleive that cobbs shelf maps already are more aggressive than this.
 
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