Tuning a Turbo P11

Has anyone added and tuned a Turbo P11 in an early 2000's 2.2L Ecotec?

The software that you can change is minimal and it appears that at idle it uses a speed/density strategy and off idle it uses an Alpha-N strategy. There is no way to change the value of the MAP sensor in the tune so going to a 2 or 3 bar MAP sensor would not calculate the BP or the correct MAP at and near idle.

My best guess would be to keep the 1 Bar MAP and then tune the Alpha-N table(s) for off idle situations with the turbo.

I may be over thinking this but just asking if I am on the right track or is there something that I am missing? If anyone has a tune that I could look at and start from also that would help.

Any input would be helpful.

You cannot use Alpha-N in boosted situations, because part-throttle you may get full boost or you may get half boost at times. Alpha-N only takes the throttle blade angle and RPM into consideration, no temperature or pressure changes.
Are you sure it's Alpha-N and not Alpha-N multiplied by MAP when off-idle?

You can hack it together by replacing the 1 bar MAP sensor with a (for example) 2 bar sensor anyway without touching the sensor calibration. This will cut the MAP values in half, when making 1 atmosphere absolute it will read as 0.5 bar MAP, and when making 1 bar of boost (2 bar MAP) it will read as 1 bar MAP in software. After that you'd have to multiply all tables which use MAP by 2 and you cut your table resolution in half. If you divide injector flow rate in half, this will cancel out and you get all the table resolution but all the logged pressure and fuel channels will be either doubled or cut in half.

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Originally Posted by sbarisic

You cannot use Alpha-N in boosted situations, because part-throttle you may get full boost or you may get half boost at times. Alpha-N only takes the throttle blade angle and RPM into consideration, no temperature or pressure changes.
Are you sure it's Alpha-N and not Alpha-N multiplied by MAP when off-idle?

You can hack it together by replacing the 1 bar MAP sensor with a (for example) 2 bar sensor anyway without touching the sensor calibration. This will cut the MAP values in half, when making 1 atmosphere absolute it will read as 0.5 bar MAP, and when making 1 bar of boost (2 bar MAP) it will read as 1 bar MAP in software. After that you'd have to multiply all tables which use MAP by 2 and you cut your table resolution in half. If you divide injector flow rate in half, this will cancel out and you get all the table resolution but all the logged pressure and fuel channels will be either doubled or cut in half.

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Thank you, truthfully I have not done a deep dive into the software to see how it reacts which is why I was asking here.

I fully understand the concept that you are outlining here, the only issue without being able to change the MAP sensor values in the software is when using a 2 bar MAP sensor the ECM will always think that it is running at the top of Pikes Peak and not somewhere near Sea Level. I could probably go through and figure out all of the math for the other effected tables but I am sure there is something that we do not have access to that would be thrown off.

Anyway thank you, I will need to do a more thorough deep dive into how the software is calculating. It would be much easier to use an E37 or E67 but both of those are for different crank pickups than the P11.