I added the code to my rom, but my MTUWGDCC tabe in the TPS column shows <.. How do I fix this?

 

this may be the final fix for my boost-spikes at low coolant temps - thanks!

 

Check to see if "ThrottlePercentage" is listed in your evo9base.xml file. I think that may be a definition that tephra added for his ROMs.

 

mrfred, these tables have completely eliminated my hi-gear knock problem.

Small request, can you define these tables for the 96530006 when you work out the direct boost patch.

 

Yea, this is a lot more useful than I think people may have originally thought.

With the maximum upward correction zero'd out, we can now re-introduce the -3 and -2 psi error correction cells that were previously zero'd to prevent overboost .

I wish I put some thought into this while I was at the track today... after zeroing max upward correction, my 4th gear boost profile showed significant taper (down to 21psi) because it wasn't pushing past my conservative WGDC of 30, plus being 2 or 3 psi off, my zero'd error correction wouldn't make any changes anyway. I wonder how much faster I would have run if I had held 25 psi...

This solves both the problem of overboost and the lost resolution in error correction we had been settling for

But anyways, I will definitely be making use of this... I'll just up my high RPM WGDC for 4th gear and I should be golden

 

Sure. :-)

 

Anyone find the addresses for 94170014/15 yet?

 

I would actually prefer max-upward correction table to be against RPM.

ie you can say 0 upward correction for 3500rpm, so you don't overshoot your desired psi!

 

MrFred or anyone else knowledgeable, can you post a screenshot of the routine in the assembly that does this? Or guide us as to what pattern or values to search for, for those of us that want to help and find this stuff for other roms.

I have IDA pro and I'm willing to look for this stuff so we can get these addresses for 9417008/14/15

 

I think having TPS and RPM would be ideal ... keep the BCS from working at part throttle and keep the correction down at low RPM and high throttle. We could also then let the BCS start working earlier (2000 RPM maybe) and spool the turbo faster without the spike.

 

So I did some logging today with the max upward correction table 0'd out.

Made the car "overboost", it pulled boost, then once it saw it was under target-load it brought BoostError Correction back to 0, but obviously no upward correction was added so BWGDC never came back to it's actual base number.

Looks like we need some upward correction set so if the boost does get pulled it can add back in WGDC to hit BWGDC again. The balancing act continues...

This was on a GT30 Evo running 29psi with an external so it was a bit more sensitive to error correction than stock turbo Evo's.

I'll post a chart here in a bit showing it...

 

so basically if you zero out upward correction then when the ECU reduces WGDC below what is defined in the baseline table it will never come back up...

 

Alright, now that I went through all the data I have a slightly different perspective on this...

First off, here are the boost tables for this Evo for reference:



Here is a normal 3rd gear pull from this Evo:



Notice that the LoadError is below zero. I did this to test to see if zeroing out the "Max Total Upward WGDC Correction vs TPS" table really did not do upward correction, even if there was additive correction numbers in the "Turbo Boost Error Correction" table. As you can see from the log above, even if you are under target load it will not add WGDC if you have the "Max Total Upward WGDC Correction vs TPS" table zeroed out and you still have additive numbers in the "Turbo Boost Error Correction" table.

So this next chart is when the car is overboosted. (overlayed with normal log from above



You will see it overboosts enough that it's almost 20 load over target load. Load error goes through the roof at almost +20, and WGDCCorrection goes to -7.5. WGDC gets pulled to 73 from the norm of 80. This brings the load down to 280 from 300 and WGDCCorrection goes back up to 0. (no additive) WGDC is brought back up to the what it should be in the table, but this creates the load to go over target, so WGDC gets brought down again. However the load still stays above target load, even with the WGDC being brought down, probably because I did not have any subtractive correction in the 2.5 and 5.0 Error Correction table.

So my take away from this, is that, with the "Max Total Upward WGDC Correction vs TPS" zero'd out, the "Turbo Boost Error Correction" table needs to be dialed in just right and quite a bit different that what I am used to doing when not zeroing out the "Max Total Upward WGDC Correction vs TPS" table. The "Turbo Boost Error Correction" table will probably will need numbers everywhere but the middle at 0.

 

Seems like something else is at-play here. In the plot with the two load curves and WGDC curves, how is it that both have the same WGDC trajectory up to ~4500 rpm but the second run builds load much faster and goes higher? Were there any other changes to the car betwen those two runs?

 

No changes. It is something I am looking into as it is very odd that it overboosted all of a sudden.

Either way it was a good exercise in how error correction will/would handle something like this.