Technical Explaining WGDC values

RSL

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PID is adding 40-45% in some spots, which is a ton. Not sure how yours is setup, but would be somewhat surprised if that's on the stock logic. When load by gear logic first came out, I tried it and simply flashing it back with the table to 0 didn't turn it off for me, I had to do a full write.

I'd add a good chunk to adder at 293 g/s and ramp up slightly from there as a quick test, but you'll obviously have more direct control working in the base table.
 
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Jake@MHD

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LPG requires a legit logic (long flash) write to remove. The setpoint table is code from BMW, simply turned on/off by the 0/1 toggle byte, no long flash required. Long flash is only required to add or remove logic that Martial or I added from scratch.
 

Jeffman

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LPG requires a legit logic (long flash) write to remove. The setpoint table is code from BMW, simply turned on/off by the 0/1 toggle byte, no long flash required. Long flash is only required to add or remove logic that Martial or I added from scratch.
The Flex Fuel tune is a long flash, correct?
 

Jeffman

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PID is adding 40-45% in some spots, which is a ton. Not sure how yours is setup, but would be somewhat surprised if that's on the stock logic. When load by gear logic first came out, I tried it and simply flashing it back with the table to 0 didn't turn it off for me, I had to do a full write.

I'd add a good chunk to adder at 293 g/s and ramp up slightly from there as a quick test, but you'll obviously have more direct control working in the base table.

I’m using the mainly stock tables and relying on good-ole PID lol. :)

Is the y-axis of the WGDC Base table Boost SetPoint? This starts to make everything clearer and easier to tune. If so, then I should probably be increasing the two columns of cells at 289 and 333 MAF of the WGDC Base table, maybe scale up each 50%?
 

Jeffman

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This obviously makes sense.
Also noting that there is no longer the simple Load per RPM table in the Flex Fuel XDF (IJEOS), just Load per Gear (per RPM).
 

Jake@MHD

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This obviously makes sense.
Also noting that there is no longer the simple Load per RPM table in the Flex Fuel XDF (IJEOS), just Load per Gear (per RPM).

That is correct. If you don't want to use the functionality, just set all gears the same. I am working on fixing the "jump" issue with LPG for AT cars though.
 
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RSL

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Is the y-axis of the WGDC Base table Boost SetPoint? This starts to make everything clearer and easier to tune. If so, then I should probably be increasing the two columns of cells at 289 and 333 MAF of the WGDC Base table, maybe scale up each 50%?
Yep. Could use the MAF adder for a broad stroke test, but I'd work in base to target setpoint where you need.
 
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WOT808

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I’m using the mainly stock tables and relying on good-ole PID lol. :)

Is the y-axis of the WGDC Base table Boost SetPoint? This starts to make everything clearer and easier to tune. If so, then I should probably be increasing the two columns of cells at 289 and 333 MAF of the WGDC Base table, maybe scale up each 50%?

From my understanding of the WGDC base table,
X= Maf Req WGDC
Y = Boost Setpoint

Probably best to make sure your x axis breakpoints line up with the maf req values in your logs. This way, the values in the bottom right hand corner of the table are your WOT cells. You may want to do the same to your WGDC Adder / Ceiling , and BLM x axis too to make things easier to manage.

In this weather, 400 maf req wgdc is around 5.5k rpm in my logs.
 
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Jeffman

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Take a look at these tables...WGDC Base and Adder are much, much higher. Took me several iterations to get here. Now I'm able to get max boost, like 22-23 psi tapering to 15 psi on stock turbos. WGDC PID maxed out at 81 and no longer interferes. Shifting 3rd-4th is very firm (xHP Stage 3) and it keeps boost up. Several timing pulls over 5000 rpm and when shifting to 4th should be cleaned up when I finally install my PR coils. This run is 93 Octane with my V1.2 Flex Fuel Custom Tune. Tomorrow we crank it up to E60! (I have a 5 gallon can of VP Racing Fuels X98 ... that's 98% ethanol ... ready to add to my 4-5 gallons of 93 Octane in the tank).

How long do you think my engine will last? I'm just under 66,000 miles and I follow Mike Miller's old-school maintenance schedule...LOL!:D

https://datazap.me/u/jeffman/flex-fuel-v12-73f?log=0&data=3-17-29-30-31&solo=3&zoom=25-129


Screenshot (15).png
Screenshot (16).png
 

RSL

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Take a look at these tables...WGDC Base and Adder are much, much higher. Took me several iterations to get here. Now I'm able to get max boost, like 22-23 psi tapering to 15 psi on stock turbos. WGDC PID maxed out at 81 and no longer interferes. Shifting 3rd-4th is very firm (xHP Stage 3) and it keeps boost up. Several timing pulls over 5000 rpm and when shifting to 4th should be cleaned up when I finally install my PR coils. This run is 93 Octane with my V1.2 Flex Fuel Custom Tune. Tomorrow we crank it up to E60! (I have a 5 gallon can of VP Racing Fuels X98 ... that's 98% ethanol ... ready to add to my 4-5 gallons of 93 Octane in the tank).

How long do you think my engine will last? I'm just under 66,000 miles and I follow Mike Miller's old-school maintenance schedule...LOL!:D

https://datazap.me/u/jeffman/flex-fuel-v12-73f?log=0&data=3-17-29-30-31&solo=3&zoom=25-129


View attachment 14231 View attachment 14232
PID was adding up to 45% in spots, so not surprised base/adder went up a lot. At least the timeouts have stopped, but ouch. Just get bigger turbos already lol I'd expect the turbos would go from shaft speeds before the motor does. I know you've been running them hard for a while, but it's essentially fully closed WGs across the board :eek:
 

WOT808

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Aug 7, 2017
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How long do you think my engine will last? I'm just under 66,000 miles and I follow Mike Miller's old-school maintenance schedule...LOL!:D

https://datazap.me/u/jeffman/flex-fuel-v12-73f?log=0&data=3-17-29-30-31&solo=3&zoom=25-129

Have you done a boost leak test recently?
WGDC is really high for that amount of boost :)

If that's max effort (no vac / boost leaks), you'd want to lower targets throughout the rpm range.
You could get close to that same boost level with less WGDC as PID/base isn't trying to reach a target a lot higher than it can grab
 
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Jeffman

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Have you done a boost leak test recently?
WGDC is really high for that amount of boost :)

If that's max effort (no vac / boost leaks), you'd want to lower targets throughout the rpm range.
You could get close to that same boost level with less WGDC as PID/base isn't trying to reach a target a lot higher than it can grab

N.b. - stock catted downpipes, stock inlets and outlets...

Good feedback. Thanks. I’ll lower the load targets when I go back to 93 pump (right now about to test E56) to see if I can get the same performance with less WGDC. I don’t suspect a boost leak as I’m experiencing the same type of boost and WGDC performance before / after pulling apart and reassembling the intake. I will check it, tho.

Thanks again.
 

iminhell1

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I'm going to jump in here because this is the thread that came up in my search.


Now what I wanted to do was run more boost, in the typical DIY fashion. On all the free tunes I'd tried I'd spike 24/25/26 psi but would never hold. Would settle around 20ish and that was it. I just don't understand enough to know what's going on and why it won't go more. Kinda made me mad for buying a N20 Tmap.
But reading through what you guys are saying I though I had a better idea of what to do. And being a risk taker I figured I'd give it a shot.
What I was pretty sure I had to do was give the WGDC (Base) table a rescale. The setpoints just didn't extend far enough beyond the stock sensors limits to offer any control.
So that's what I did.

Seems to have done the trick in a rough and dirty fashion (and yes I snipped the good section out of a longer log, it's WIP),

https://datazap.me/u/iminhell1/log-1558909489?log=0&data=3-21
 

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