Notices
ECU Flash

how-to: ECU-based direct boost control

Thread Tools
 
Search this Thread
 
Old Sep 11, 2007, 11:46 PM
  #61  
Evolved Member
iTrader: (11)
 
mchuang's Avatar
 
Join Date: Sep 2005
Location: h town
Posts: 2,180
Likes: 0
Received 1 Like on 1 Post
ok nm, i see the axis on the opposite side my bad
Old Sep 12, 2007, 07:59 AM
  #62  
EvoM Guru
Thread Starter
iTrader: (50)
 
mrfred's Avatar
 
Join Date: Mar 2006
Location: Tri-Cities, WA // Portland, OR
Posts: 9,675
Received 128 Likes on 96 Posts
Originally Posted by mchuang
Wow that is nice, what do you use to plot graphs mrfred?
Its a template I made up in Excel. I have an older version posted here somewhere. Its setup for easy cut and paste from my EvoScan files. I'm thinking of automating it so that it can plot data from anyone's EvoScan file. Its pretty far down the list at the moment.
Old Sep 12, 2007, 07:10 PM
  #63  
Evolving Member
iTrader: (3)
 
RedV's Avatar
 
Join Date: Mar 2005
Location: Grand Rapids, MI
Posts: 222
Likes: 0
Received 0 Likes on 0 Posts
I think I'm getting there mrfred...



... There's a little dip between 4500-5000 RPM so I'm gonna give it a little bump there to see if I can correct that. Otherwise I'm thinking it looks good.
Old Sep 12, 2007, 07:21 PM
  #64  
Evolved Member
iTrader: (6)
 
nj1266's Avatar
 
Join Date: Nov 2004
Location: USA
Posts: 3,254
Likes: 0
Received 13 Likes on 3 Posts
Can anyone translate these formulas into language that Logworks can understand?

<DataListItem DataLog="Y" Color="" Display="Boost Error" LogReference="BoostError" RequestID="8A" Eval="0.0241*x-3.087" Unit="psi" MetricEval="" MetricUnit="" ResponseBytes="1" GaugeMin="-5" GaugeMax="5" ChartMin="-5" ChartMax="5" ScalingFactor="1" Notes=""/>
<DataListItem DataLog="Y" Color="" Display="WGDC Correction" LogReference="WGDCCorr" RequestID="8B" Eval="0.5*x-64" Unit="WGDC%" MetricEval="" MetricUnit="" ResponseBytes="1" GaugeMin="-50" GaugeMax="50" ChartMin="-50" ChartMax="50" ScalingFactor="1" Notes=""/>
Old Sep 12, 2007, 10:00 PM
  #65  
EvoM Guru
Thread Starter
iTrader: (50)
 
mrfred's Avatar
 
Join Date: Mar 2006
Location: Tri-Cities, WA // Portland, OR
Posts: 9,675
Received 128 Likes on 96 Posts
Originally Posted by RedV
I think I'm getting there mrfred...

...

... There's a little dip between 4500-5000 RPM so I'm gonna give it a little bump there to see if I can correct that. Otherwise I'm thinking it looks good.
Yep, its getting there. Looks like another 5-8% BWGDC can be added from about 4250-5000 rpm? A bit more fine tuning after that maybe. I attached my latest spreadsheet if you want to use that.
Attached Files
Old Sep 13, 2007, 08:56 PM
  #66  
Evolved Member
iTrader: (6)
 
nj1266's Avatar
 
Join Date: Nov 2004
Location: USA
Posts: 3,254
Likes: 0
Received 13 Likes on 3 Posts
Tonight I implemented direct boost control on my car. But the logs left me with a few questions. Here is one of the logs. I did them in Evoscan, but I am reading them in Logworks.

1. I am not hitting the boost that I entered in the baseline boost tables. I attached the tables. I am using the same WGDC setting that I used with the Load system. Is that to be expected? Do we have to run higher WGDC with the direct boost system than with the load boost system?

2. Could someone explain to me how boost error relates to my actual boost? Does it work this way: At 5656 rpm my actual boost is 17.22, but the boost error is -2.70 psi. If I add them together I get 19.92 psi which is close to 20.1 psi in my baseline boost table. If that is the way this works, then how can I counteract it from happening. What do I do to hit my baseline boost of 20.1 psi?

Attached Thumbnails how-to: ECU-based direct boost control-psi_boost.gif   how-to: ECU-based direct boost control-psi_tables.gif  
Old Sep 13, 2007, 10:05 PM
  #67  
EvoM Guru
Thread Starter
iTrader: (50)
 
mrfred's Avatar
 
Join Date: Mar 2006
Location: Tri-Cities, WA // Portland, OR
Posts: 9,675
Received 128 Likes on 96 Posts
Originally Posted by nj1266
Tonight I implemented direct boost control on my car. But the logs left me with a few questions. Here is one of the logs. I did them in Evoscan, but I am reading them in Logworks.

1. I am not hitting the boost that I entered in the baseline boost tables. I attached the tables. I am using the same WGDC setting that I used with the Load system. Is that to be expected? Do we have to run higher WGDC with the direct boost system than with the load boost system?

2. Could someone explain to me how boost error relates to my actual boost? Does it work this way: At 5656 rpm my actual boost is 17.22, but the boost error is -2.70 psi. If I add them together I get 19.92 psi which is close to 20.1 psi in my baseline boost table. If that is the way this works, then how can I counteract it from happening. What do I do to hit my baseline boost of 20.1 psi?
The BEC table I recommend is very conservative in the sense that if the actual boost is more than 1.4 psi below the target boost, the system will not try to increase the WGDC to compensate. In the BEC table, this is represented by the zeros at -1.4, -2.0, and -3.1 psi.

In your situation, you were below your target by almost 3 psi, so the BEC system didn't try to fix it. You'll need to increase your BWGDC table in those areas where the boost was off by that much. Alternatively, you could change the zeros at -1.4, -2.0, and -3.0 psi to 1's or 2's, but I don't recommend this because it can lead to boost overshoot during spool. I think its better to have a BWGDC curve that provides the desired boost with minimal corrections. If I'm reading your logworks plot correctly, the boost was more than 1.4 psi below the target boost for the entire run. I'd recommend increasing the BWGDC curve by maybe 5% across the board. Maybe increase it even more in the areas where the boost was 3 psi below the target.

The direct boost control system does not affect the BWGDC tables in any way. I'm guessing what happened is that with the load based setup you were using before, the ECU was correcting the WGDC upward during spool because of you were non-zero values in the upper right of the TBEC table.
Old Sep 13, 2007, 10:21 PM
  #68  
Evolved Member
iTrader: (6)
 
nj1266's Avatar
 
Join Date: Nov 2004
Location: USA
Posts: 3,254
Likes: 0
Received 13 Likes on 3 Posts
Originally Posted by mrfred
The direct boost control system does not affect the BWGDC tables in any way. I'm guessing what happened is that with the load based setup you were using before, the ECU was correcting the WGDC upward during spool because of you were non-zero values in the upper right of the TBEC table.
In the load based set-up I was using the stock TBEC table. Could that be the reason for the lower BWGDC in the load set-up?

also, could you tell me if my understanding of the way the BEC relates to actual boost is correct? Is it as I stated before: At 5656 rpm my actual boost is 17.22, but the boost error is -2.70 psi. If I add them together I get 19.92 psi which is close to 20.1 psi in my baseline boost table.
Old Sep 13, 2007, 10:25 PM
  #69  
EvoM Guru
Thread Starter
iTrader: (50)
 
mrfred's Avatar
 
Join Date: Mar 2006
Location: Tri-Cities, WA // Portland, OR
Posts: 9,675
Received 128 Likes on 96 Posts
Originally Posted by nj1266
In the load based set-up I was using the stock TBEC table. Could that be the reason for the lower BWGDC in the load set-up?

also, could you tell me if my understanding of the way the BEC relates to actual boost is correct? Is it as I stated before: At 5656 rpm my actual boost is 17.22, but the boost error is -2.70 psi. If I add them together I get 19.92 psi which is close to 20.1 psi in my baseline boost table.
Yes, and Boost Error is the difference in psi between the target boost and the actual boost as you were guessing.
Old Sep 13, 2007, 10:27 PM
  #70  
EvoM Guru
iTrader: (8)
 
RazorLab's Avatar
 
Join Date: Aug 2003
Location: Mid-Hudson, NY
Posts: 14,065
Received 1,038 Likes on 760 Posts
nj, you need more cowbell.
Old Sep 13, 2007, 11:13 PM
  #71  
EvoM Guru
iTrader: (6)
 
tephra's Avatar
 
Join Date: Feb 2007
Location: Melbourne, Australia
Posts: 9,486
Received 66 Likes on 42 Posts
this is great stuff guys - congrats Mr-Fred I'm tempted to get rid of my boost controller But alas I need a gauge + MAP ... hehe
Old Sep 14, 2007, 08:30 AM
  #72  
Evolved Member
iTrader: (6)
 
nj1266's Avatar
 
Join Date: Nov 2004
Location: USA
Posts: 3,254
Likes: 0
Received 13 Likes on 3 Posts
Originally Posted by razorlab
nj, you need more cowbell.
Explain please
Old Sep 14, 2007, 08:36 AM
  #73  
Evolved Member
iTrader: (6)
 
nj1266's Avatar
 
Join Date: Nov 2004
Location: USA
Posts: 3,254
Likes: 0
Received 13 Likes on 3 Posts
mrfred,

Why did you set-up the range on the BEC table from 3.1 to -3.1? Why not use the stock range? Just curious

When I modified the xml file, I noticed that the TBEC table (the one that I use for load based boost) also changed its range. I had to make two xml files/base files and swap them around to get around this issue.
Old Sep 14, 2007, 09:02 AM
  #74  
EvoM Staff Alumni
iTrader: (16)
 
MR Turco's Avatar
 
Join Date: May 2007
Location: Massachusetts
Posts: 3,233
Received 3 Likes on 3 Posts
Originally Posted by razorlab
nj, you need more cowbell.
LOL
Old Sep 14, 2007, 09:07 AM
  #75  
Evolved Member
iTrader: (7)
 
mplspilot's Avatar
 
Join Date: Oct 2006
Location: Flyover country.
Posts: 1,439
Likes: 0
Received 1 Like on 1 Post
I think i need more cowbell as well


Quick Reply: how-to: ECU-based direct boost control



All times are GMT -7. The time now is 02:35 AM.