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Old 11-07-2017 | 12:41 PM
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Default Boost by Speed/Gear

Has anyone managed to use boost by speed/gear settings with success? I started playing around with setting it up last night, but it didn’t work right for me. I was hoping to bounce some ideas off you guys and see if I could get it ironed out.

It doesn’t look like my gear settings are logging correctly for me so I went with boost by speed to test it out. Right now I have 3 boost settings; 170kpa wastegate, 210kpa target table 1, and 220kpa target table 2. The software allows me to set up boost by speed as well as the 2 target tables. I assumed that the boost by speed table would then just set an upper limit when speed is below the target table.

I attempted to test this by setting the boost by speed table to:
0mph – 190kpa
30mph – 200kpa
40mph – 210kpa
50mph – 221kpa
60mph – 223kpa
70mph – 223kpa

My hope was that when using boost table 1 the car would use the boost by speed table up to 40mph, then it would just hold 210kpa commanded by table 1. On boost table 2 I was hoping to use the boost by speed table to 50mph, then hold 220kpa. Is my understanding of how that works correct or does the boost by speed table completely override the target tables (so the car would run whatever the boost by speed table indicates regardless of target table)?

On my drive this morning, the car initially targeted 190kpa and would gradually creep up to 192kpa by a logged VSS1 of 70mph. I feel like the chart is working somewhat in order to target the 190kpa that’s not targeted elsewhere, but for some reason it’s not increasing with speed.

If anyone has suggestions or input please let me know. If not I’ll keep playing with it a little and sharing my progress, or lack thereof. If anyone is interested in digging through the tune or a log I can post it this evening when I get home. Hopefully I can get this working and pull some boost in 1st and 2nd gear.
Old 11-07-2017 | 02:23 PM
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I have never tested Boost By Speed, but I can say that Boost By Gear does indeed totally override target tables, so I presume BBS would as well.

I did not like losing the target tables using BBG.

I don't like the idea of BBS as wheel spin ups the boost. Of course, you would be backing off throttle anyway, but throttle position is now not tied to reduced boost levels.

I think the best approach, suggested by @aidandj, is to use (2) boost tables switched by gear. (option is above BBG). If I understand it, you set table 2 for lower boost, and then choose at what gear you would like to have MS3 move to table 2.

This gives lower boost, still controlled by TPS in say, 1 & 2, and then when you shift into 3rd, the higher table comes into play.

I have not tried this, but others have, I think Bronson.

This will require gears to be logging correctly. If you have correct speed, AND correct transmission and differential data, gears should be correct.
Old 11-07-2017 | 02:26 PM
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Post log and tune. That will help a lot.

You can also look at the Boost Target field. This will show you what you are targeting.

I haven't used boost by speed.

You can do non linear things by using a Blend Curve to blend boost, and then using speed as one of the axis.
Old 11-08-2017 | 09:48 AM
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Ahh, I forgot to post the tune and log from home last night. The boost target field was targeting 190kpa and only went up to 192kpa by 70mph.

If boost by gear overrides the target tables then I'll probably just abandon the idea. I really like having my 3 boost settings, I'd rather just control spin in 1st and 2nd with the right pedal than give up those.
Old 12-11-2018 | 07:20 PM
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Default Boost By Gear and tables a Reality

I now have boost by gear working as it should. Key is to set up Tables 1 and 2, then blend them by gear.

1) Set up Closed Loop EBC
2) Table 1 is low boost, Table 2 is full boost
3) Set Switching to Blend Curve 6
4) Go to "Table Choices / Blend Curve 6"
5) Make X Axis Gear
6) I set mine up thus for testing:



100% means table 2 rules. 0% Means Table 1 rules.

Here are my Tables 1 and 2 (150 is waste gate pressure):


7) Make sure your VSS and Gear ratios are set up. In my case MS3 had trouble discerning 4 from 3 and 5 from 4, so I cheated 4 and 5. Instead of 4 = 1.00, I made it 1.05. Similarly, instead of 5 = 0.81, I made it 0.93. Now MS hits them dead on. Those things are set up under "Advanced Engine / Speed and Gears". Well 4th is not perfect, as you can see in log where it skipped to 5th for a moment, but you get the idea. I may have overdone 5th adjustment.

That is it. Still have boost proportional to throttle position, but also the targets are a blend of the tables, however you want to set them up.

For me, it will likely be 1=0; 2=40; 3=70, 4 and 5 =100% for the winter.



Old 12-11-2018 | 10:19 PM
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Nice, stingy cat awarded
Old 12-12-2018 | 12:16 AM
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Note: you may wish to swap the tables so that if you revert back to a single one, it is the full boost one.

Mine are the way they are because I was using switch at gear, so I was forced to use table 1 for the low boost in 1st and 2nd, then went to full table upon switch to 3rd.
Old 06-15-2019 | 01:49 AM
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Yer a got damned genius.

I'm setting mine up for boost vs VSS and super excited to try this. I'll report back.

Also, how would I go about getting Boost Control Bias Table 2
Old 06-15-2019 | 03:41 AM
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I don’t know. I don’t use it. Not needed for the above scenario. While it is true that when using the blended targets, the same target is called for at a different throttle position, I’ve not found that to be a significant variable.

Any throttle position above about 25% is more of a potentiometer input than a flow control.

Does that make sense?

DNM
Old 06-15-2019 | 11:28 AM
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OH! of course. Thank you for straightening that one out.
Old 06-16-2019 | 11:39 PM
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AWESOME. Boost by speed finally. this is an example of some throttle modulation.

Old 06-16-2019 | 11:47 PM
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