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Old 10-05-2006, 01:56 PM   #151
fasterthanurwrx
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AZScoobie-

Wanna email me those maps!

With all kidding aside, is there any other pointers you can give?

Thanks
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Old 10-06-2006, 12:22 AM   #152
AZScoobie
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Sure! I give all my maps for free!!!! Here is my Stock turbo AVCS map and my Large turbo map!

000000000
000000000
000000000
000000000
000000000
000000000
000000000

333333333
333333333
505050505
505050505
505050505
50505050
5050505050
50505050
5050505
505050
494
49
494
44
4
958
4
00

Try that one!



I am not sure what else to say in this thread. I believe I have helped a great deal.

Cya

Clark
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Old 10-06-2006, 07:51 PM   #153
keyser_soze
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Quote:
Originally Posted by AZScoobie View Post
Sure! I give all my maps for free!!!! Here is my Stock turbo AVCS map and my Large turbo map!

000000000
000000000
000000000
000000000
000000000
000000000
000000000

333333333
333333333
505050505
505050505
505050505
50505050
5050505050
50505050
5050505
505050
494
49
494
44
4
958
4
00

Try that one!



I am not sure what else to say in this thread. I believe I have helped a great deal.

Cya

Clark
wait...do we need to print this put lime juice on it and hold it infront of the candle light then take into frequency domain and do a FFT to get an equivilant of the the good ol screen shot! haha

i'm not saying share away ... completely understandable if you choose not to...but if its a joke i'm missing it....since it would take 5 min or so to type what you typed up there...
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Old 10-09-2006, 03:06 PM   #154
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Its a secret code... You need a 1985 model Decoder ring from a Cracker jack box to decode it..

Clark
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Old 10-10-2006, 09:34 AM   #155
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this thread may be of interest to some, as it talks a bit about egbp, map, the ratio between the two, etc.

no direct discussion of avcs though. for that you'll have to read between the lines.

http://bbs.22b.com/cgi-bin/ultimateb...;f=8;t=001117;
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Old 10-10-2006, 05:08 PM   #156
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So can anyone give me any pointers as to where to start the tuning process (safely) for AVCS with AEM EMS ? I know there is a section in AEM about Variable Valve control, but not exactly sure if that is what we want to use. I cant seem to find anyone that has attempted this.

btw - I have a EJ257 block with ported EJ207 heads.
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Old 10-10-2006, 05:32 PM   #157
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I'll tell you how I would do it.

I'd know my fuel and spark maps well and know where the engine spends time (load/RPM). You can't tune everywhere, and a several points will get you 95% of the map.

I'd start with good tune.

I'd advance AVCS by 5% and look at torque and general engine performance (no bucking, no super lean/rich AFR). Reiterate another 5% and watch torque the whole time. I'd look for a trend in advancing AVCS and gaining torque. I would also adjust AFR if things got too rich/lean in the load sites being AVCS advanced. Small changes are key here.

I would carry out the same procedure at several load sites both in vacuum and in boost on a load adjusting dyno. By driving at a single load site you can make adjustments and see the effect on torque immediately.

For very high load (near highest boost and highest boost) and high RPM (4000-up), I think I would just use full 4th gear pulls to look for any AVCS advantage up top and also get some AFR data and EGT data to do any fine tuning of AFR and spark timing.

Then I would smooth the AVCS map between the load points and fill untouched areas with best guesses based on published AVCS maps.
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Old 10-10-2006, 05:52 PM   #158
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Quote:
Originally Posted by kpowell12 View Post
So can anyone give me any pointers as to where to start the tuning process (safely) for AVCS with AEM EMS ? I know there is a section in AEM about Variable Valve control, but not exactly sure if that is what we want to use. I cant seem to find anyone that has attempted this.

btw - I have a EJ257 block with ported EJ207 heads.
THe AEM will not control the STI's variable intake cams.

Clark
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Old 10-11-2006, 03:12 AM   #159
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Quote:
Originally Posted by AZScoobie View Post
THe AEM will not control the STI's variable intake cams.

Clark
So I might as well have gotten stock WRX heads instead of spending extra money on the ej207 heads? . I thought for sure there would be a way to do it in AEM.
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Old 10-11-2006, 05:43 AM   #160
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Quote:
Originally Posted by kpowell12 View Post
So I might as well have gotten stock WRX heads instead of spending extra money on the ej207 heads? . I thought for sure there would be a way to do it in AEM.
...no...ya got the right heads....ya need ta ditch the AEM
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Old 10-11-2006, 10:47 AM   #161
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The AEM EMS definitely has the *capability* to control the AVCS, but the base maps won't be configured to do so (since USDM non-DBW WRX = no AVCS, much less AVCS wiring).
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Old 10-11-2006, 11:24 AM   #162
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Quote:
Originally Posted by x99percent View Post
The AEM EMS definitely has the *capability* to control the AVCS, but the base maps won't be configured to do so (since USDM non-DBW WRX = no AVCS, much less AVCS wiring).
Correct.

If you're using a JDM ECU. I can find out the name of a shop that builds a PEMS type harness that lets you piggy back the factory ECU to the EMS. That way you can let the factory ECU control cam advance, while the EMS does everything else. That setup is how STI's are able to run the EMS with the DBW setups.

-Jorge
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Old 10-11-2006, 11:30 AM   #163
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The AEM will not control the Subaru AVCS. It has no ability to read the cam sensors to locate the Cams and adjust duty cycle. Its a closed loop system. The Hydra blindly pulses the cams but its a crap shoot as to where the cams actualy are.. You or the hydra has no idea and the left and right banks are independant so you have an imbalance.

The two best options are Utec with Speed density over Stock ecu or the LINK G3 plugin.

Clark
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Old 10-11-2006, 11:57 AM   #164
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Quote:
Originally Posted by AZScoobie View Post
The AEM will not control the Subaru AVCS. It has no ability to read the cam sensors to locate the Cams and adjust duty cycle. Its a closed loop system.
I heard about the "capability" directly from a "reputable source". I can't say any more than that. [shrug]

Eventually, the DBW AEM EMS boxes will come out, and they won't be piggybacking anything.

Quote:
Originally Posted by AZScoobie View Post
The Hydra blindly pulses the cams but its a crap shoot as to where the cams actualy are.. You or the hydra has no idea and the left and right banks are independant so you have an imbalance
STi Hydra = closed-loop AVCS control, just to clarify.
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Old 10-19-2006, 08:30 PM   #165
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well just a update
i know it is the wrong way some would say but kienan used the wastegate table and built a map useing the aem today
started off low in the lower rpm sections and tuned from there
got a little more from the bottom end
just need to find a rig to read the front and rear sensor to see change
here is a comparison chart
gained about 40 ft lbs
beleive the map he made only runs in a 2000 range
http://i33.photobucket.com/albums/d9...comparison.jpg

Last edited by Vmiz; 10-19-2006 at 08:36 PM.
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Old 12-07-2006, 04:06 AM   #166
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Here's some test data I collected...

What I did was set timing to 12 degrees fixed and then set the AVCS advance to 0 degrees advance, 10, 20, 30 and 40 degrees and captured injector time and AFR (via wideband AFR).

This allowed me to calculate cylinder load at each given data capture point (the total mass of air in all cylinders at the point of capture), which is simply based upon the injector time at each data capture point and the measured AFR at the data capture point. I have assumed my injectors flow 565cc/min and that fuel has a mass of 0.76g/cc. This calculated engine load is directly proportional to mass air flow.

Here are the results (note that I stopped the 30 degree and 40 degree runs early as I know that much advance isn't very good at high RPMs):

Mass Air Flow


Measured AFRs


The differences are interesting. In theory, the mass air flow graph should be what you work from, but the 20 degree advance result is somewhat misleading at high RPMs. The mass air flow graph indicates 20 degrees advance is better at high RPMs than 0 degrees advance - this is definitely not the case, based upon seat of pants and the fact the car is running about 2PSI more boost with 20 degrees advance at high RPM, indicating the engine is more restricted.

Based upon the mass air flow graph, these would be the optimal AVCS settings (assuming your map uses 250RPM increments:

4000RPM: 40 degrees advance
4250RPM: 30 degrees advance
5000RPM: 20 degrees advance
5750RPM: 10 degrees advance

Based upon the AFR graph, these would be the optimal AVCS settings (assuming your map uses 250RPM increments:

4000RPM: 40 degrees advance
4750RPM: 30 degrees advance
5500RPM: 20 degrees advance
6500RPM: 10 degrees advance
7500RPM: 0 degrees advance

Next time I'm on a dyno I'll repeat this exercise and see which of the above (calculated mass air flow or AFR) is more aligned with power output...
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Old 12-07-2006, 05:50 AM   #167
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Good stats
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Old 12-07-2006, 08:59 PM   #168
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Hehe... Pretty good data.

Clark
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Old 12-07-2006, 09:40 PM   #169
ride5000
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good work!
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Old 12-07-2006, 11:32 PM   #170
heet
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that's pretty cool.
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Old 12-08-2006, 03:15 PM   #171
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I thought I would make a suggestion about tuning the AVCS from the graphs that you posted... I am not sure that the first one is correct, based on the way you did it, but the second one shows some promise... The way you did it, leaning out means more air got thru the engine...

Next time you do your test, you might want to try this...

Set your Cam map to 40 degree until your turbo is starting to spool... Ie about 1/2 of the psi it can generate... run the mixture about 12.5 up till that point... after that run it as lean as you like to tune for the setup...

Take the point that your turbo psi peaks, and make that 20 degrees...

at 5250 you should be down to 10 degrees, maybe lower...

By 6000 you should be at 0 degrees...

Right before your limiter, say 750-1000 before, climb back up to about 5 or 10...

Now smooth out the curve so there are not any abrupt changes in the curve of the AVCS map...

Now tune it so all your mixtures stay right... But leave timing at 12 degrees, then re-run your test, on a dyno... Look only at the torque curve, It may be quite erratic at first, but you can flatten it out on the lower end by tweaking the cam map, and the upper end with the timing and the mixture... Try to get as much torque as possible across the entire rpm range... If you tune your car this way, it may not make the horsepower that other tunes make, but the torque curve will speak for itself in the real world...

To do the test you are doing correctly, you should make maps for each point that keep the mixture correct... Proper mixture will have a dramatic effect on the amount of air going thru the motor... you will also have to keep the boost flat the entire time...

Just my 2 cents....
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Old 12-08-2006, 10:40 PM   #172
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AVCS targets depend HEAVILY on the cams currently in the car. The JDM spec c that STI8U has will have a different AVCS curve than the USDM STI. Everyone needs to keep that in mind.

Furthermore, AFAIK, the USDM STI can only use a max of 30d (but somehow the '07 USDM STI uses 40d in some places - hmph. The heads changed for '07. Any chance they changed the cams too?

t
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Old 12-09-2006, 03:16 AM   #173
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Quote:
Originally Posted by shvrdavid View Post
I thought I would make a suggestion about tuning the AVCS from the graphs that you posted... I am not sure that the first one is correct, based on the way you did it, but the second one shows some promise... The way you did it, leaning out means more air got thru the engine...

Next time you do your test, you might want to try this...

Set your Cam map to 40 degree until your turbo is starting to spool... Ie about 1/2 of the psi it can generate... run the mixture about 12.5 up till that point... after that run it as lean as you like to tune for the setup...

Take the point that your turbo psi peaks, and make that 20 degrees...

at 5250 you should be down to 10 degrees, maybe lower...

By 6000 you should be at 0 degrees...

Right before your limiter, say 750-1000 before, climb back up to about 5 or 10...

Now smooth out the curve so there are not any abrupt changes in the curve of the AVCS map...

Now tune it so all your mixtures stay right... But leave timing at 12 degrees, then re-run your test, on a dyno... Look only at the torque curve, It may be quite erratic at first, but you can flatten it out on the lower end by tweaking the cam map, and the upper end with the timing and the mixture... Try to get as much torque as possible across the entire rpm range... If you tune your car this way, it may not make the horsepower that other tunes make, but the torque curve will speak for itself in the real world...

To do the test you are doing correctly, you should make maps for each point that keep the mixture correct... Proper mixture will have a dramatic effect on the amount of air going thru the motor... you will also have to keep the boost flat the entire time...

Just my 2 cents....
The first graph is calculated as follows:

Air Mass = Injector Time (ms) x Injector Flow (cc/ms) x Fuel Specific Gravity (0.76) x AFR ratio

I think air mass in theory SHOULD indicate what cam advance is optimal, because if you look at just the AFRs, a richer reading could be due to the ECU injecting more fuel. Of course you could use just the AFRs if the ECU injected the same amount of fuel for each run, but that doesn't happen.

The one thing that I still haven't quite got my head around is that the reason the 20 degree advance setting is giving such a high air mass figure at high RPMs is because the boost is higher. Even though the boost is higher, you can feel the power output is much reduced, indicating the higher boost is due to the fact the engine is actually physically pumping less air. This is indicated by the rich AFR readings for 20 degrees advance, however using my formula above, the mass of air being pumped is still higher?!? It could be an error in my formula I guess.
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Old 02-06-2007, 07:29 PM   #174
west_minist
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Guys,

I will be testing AVCS from 0-50 set in all zones on the JDM STI Spec C.

The car is located at the following links below.

http://socob.bb/forum/viewtopic.php?t=237
http://socob.bb/forum/viewtopic.php?t=225&start=15
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Old 02-06-2007, 08:17 PM   #175
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Here's some more toying.


( I dunno why you have to click this, I have img tags on it... sigh)

I've got Engine load vs. RPM here. This is purely because the AVCS map is built this way, thus I want to use the same metrics to build a 3D map. The data points then are MAP (specifically, Ecuedit averages all the points for me). It may seem counter intuitive at first glance, but I want to see the lowest possible MAP at each RPM and load point. Because a lower MAP at the same RPM and load means the engine is flowing air more efficiently, taking less manifold pressure to flow the same amount of air.

By switching back and forth between several logs (each with a different AVCS tune), I can see which map has the best flow.

For instance, if I have two logs and one shows only 15psiA at 1.3 load, 3200rpm, and the other 16.5siA at the same load and RPM, the first log is giving me better flow. Thus I would look at the AVCS numbers for each log run and use the first one in that portion of my AVCS map.
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