Flyin EVO 2

I searched the forum and I have not been able to find one clear post on how the boost control works. Which maps control what function and to what degree? What map controls what other maps (which maps work the same settings for different values?). I'm having a boost searching situation where the boost isn't coming on smoothly and is fluctuating. I've adjusted boost target as well as gear dependent settings and no matter where the settings are it searches for boost. A clear cut answer or link to a clear cut and dry answer would be greatly appreciated.

RoadSpike

iTrader: (5)

Edit:
Editing some names so they make more sense to the table structure

Plenty of things to note.

First the boost target is a combination of the boost adder table and the desired boost table.

So target is simply adder + desired = target boost.

The boost is in psiA which means you need to add 14.5 to get it beyond atmospheric pressure.

The control is a feedback loop so simply it looks up target boost pressure as above and subtracts that from the current boost.

So boost error = current boost - target boost.

Boost error is used to look up the boost error table left hand column and it applies the correction in the interval (ms) found in the global boost settings.

Log boost error and correction to get an idea what correct is being made if any and what boost target its expecting. Commonly 0 out the lowest correction value, the one on the top, so when the turbo is spooling up its not trying to correct it to a value.

One other thing to note is the feedback loop works something like a fuel trim so it keep the correction until the error table corrects it back out. So If you have large corrections in your error table its going to bounce back and forth between over boost and under boost.

Lastly as you reduce the interval time down to the minimum of 1 you need to use less correction adjustment %. If you use larger % values you'll end up cycling from over boost to under boost. To help modulate this type of behavior typically have stronger downward correction and milder upward correction. You essentially want the target to stop hitting the bad ceiling spot but don't want to rush to the goal so you overshoot.

Flyin EVO 2

Here are all of the tables of adjustment available on the left hand collum of ECU Flash when I pull up the map

MAF IAT WGDC correction
TPS WGDC correction
Base Wastegate Duty
Boost Desired Engine Load

First off the "Boost desired Engine Load" goes from 0 to 159.4. I'm assuming this is an absoloute value, not a refrence to boost or kpa? Second The "Base waste gate duty" is the amount the solenoid is being controled (closed/open) or is this the gain setting? I lowered the "TPS WGDC Correction" and the searching improved vastly, but it still searched. I then lowered the "Boost desired engine load" from 159.4 to 84, and the searching went away, but the boost dropped to 12 psi.?! The wastegate duty was up in the 70's, and only 12psi??? "MAF IAT WGDC" is at 0. What am I missing??? What needs to be set where for 20 psi and no searching???

Raptord

iTrader: (10)

Zero out boost error correction to start with. Put conservative values (ie. 50%) in your base wastegate duty cycle table for all gears across the whole rpm range. Now start doing pulls and seeing what you need to adjust. Increase WGDC to increase boost, opposite to lower boost. Once you've got your boost pretty much the way you want it in every gear, you can set up your target boost tables and finally turn back on boost error correction, which will allow the ECU to compensate for changes in temp, etc.

RoadSpike

iTrader: (5)

What Rom ID are we using FlyinEvo2?

Engine load is not directly tied to kPa but its semi close till you hit higher boost numbers. If your using the old load based system you'll see a table called boost control load offset. Thats the same table as boost adder in my rendition.