GMPP Stage I (Delta) and Stage II (Kappa) Discussion

[More_Torque_More_HP]

Originally Posted by OneBullet

still waiting for stage kit...

The kit should be out soon for the 2009's. I will post as soon as it is released!

[DEJON-Dave]

Back in Dec, I had the GM tune upgrade installed on my 07 Solstice GXP. Saturday I finally got around to some major testing. I've got on of my Mitsu EVO3 16g kits on my car and use a manual boost controller. I modded the airload and other tables as with the previous stock tune.
1. This tune accepted 28psi for more than 3 sec without going into limp mode. The stock tune even with major changes in airload table, etc would not allow more than 23psi for 3 sec.
2. The DIC did not read over 23psi boost even with the new sensors. HP Tuners read 255kpa on the MAP and flatlined when I went over 23psi. So I could not read true boost in a scan.
3. I hooked up the stock Boost Control Solenoid but could not get the ECM to control it. I gave it many cycles to "learn" and key restarts also. I think there must be boost control tables that we cannot change yet limiting the ECM's ability
4. I increased the rev limit to 7000 without problems.
5. The ECM held commanded AFR. I've installed an MSD fuel pump booster it insure pressure.

[More_Torque_More_HP]

Hi All, Here is another dealer install issue that was found. If you have a P0236 after your install the most likely cause is the dealer wired the TAMP sensor in the inlet duct exactly backwards. They used pin#4 as pin#1, pin#3 as pin#2, Pin#2 as Pin#3 and Pin#1 as pin#4.

Bill

[AaronSS]

Originally Posted by DEJON-Dave

1. This tune accepted 28psi for more than 3 sec without going into limp mode. The stock tune even with major changes in airload table, etc would not allow more than 23psi for 3 sec.
2. The DIC did not read over 23psi boost even with the new sensors. HP Tuners read 255kpa on the MAP and flatlined when I went over 23psi. So I could not read true boost in a scan.

1. How were you reading boost levels?
2. This is something shabby and I were talking about, and is exactly what I expected.


Here is a question for Bill. On the HHR and Cobalt, where does the stock analog boost signal come from?

[krispy]

turbo MAP would be my guess

[More_Torque_More_HP]

Originally Posted by AaronSS

1. Here is a question for Bill. On the HHR and Cobalt, where does the stock analog boost signal come from?

The analog Boost signal is taken from the MAP sensor on the engine.

[AaronSS]

Originally Posted by More_Torque_More_HP

The analog Boost signal is taken from the MAP sensor on the engine.

So because the 3bar map sensor output is in the same range as the stock 2.7 bar, stage tuned cars won't see true boost.

[More_Torque_More_HP]

Originally Posted by AaronSS

So because the 3bar map sensor output is in the same range as the stock 2.7 bar, stage tuned cars won't see true boost.

the maixum volts out and the minimum volts out of the 3 bar is the same as 2.7 bar. The scaling is different as interpreted by the ECM. The analog out put is in volts. as an example (the volltages are changed to protect the inocent): the 2.7 bar had low reference in (ground) and 5 volts in. The out put would be 0 volts for zero absolute pressure and 5 volts for 2.7 Bar absolute pressure or 1.85 volts per bar pressure. The analog signal of the 3 bar sensor would 0 for zero absolute and 5 volts for 3.0 Bar or 1.67 volts per bar pressure. The computer interprets them based on the calibration. Now to get more boost you just can not change sensors because there is a rationality check at key up between 3 sensors. The MAP, TMAP and the baro sensor (which is located inside the ECM). if you change the sensors and the programing is not change the rationality check will fail and set a code and default to no boost.

[cobaltssoverbooster]

ya but we can turn codes off correct, would that allow to keep making boost?

[1WhiteSSTC]

Originally Posted by cobaltssoverbooster

ya but we can turn codes off correct, would that allow to keep making boost?

u can clear the code but it will just come back when the rationality check cycles........each time the car is turned on? every few minutes??