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KanosWRX said:
I thought the Turbo XS unichip did not need a separate boost controller, unless you wanted to adjust boost because you were at a different altitude. Does the Unichip increase any boost by itself, and if so to how much? Their page also says this about the chip

Built in part throttle boost controller (<=30%) limited to 7psi -
Protection from high boost when factory ecu runs in closed loop @ 14.7:1 air fuel ratios. Factory boost level is 7psi and when using aftermarket electronic and manual boost controllers, full boost can be reached at partial throttle, resulting in high exhaust gas temperatures and lean run conditions.

I guess I don't understand exactly how the unichip, or for that matter the stock ECU differs from the EBC in the sense of how it controls boost at different throttle positions. Does the ECU control the boost at different throttle positions the same way as the Unichip would? And with a EBC it has 4 boost levels, so you could do 25% boost at 25% throttle, 50% at 50% and so on.
Stock ECU does control boost based on throttle position. It will give you full boost after 58% TPS, when it goes open loop. Anywhere below that, it will run in closed loop mode, maintaining 14.7:1 A/F ratio and around 8 psi of boost (wastegate spring pressure).
 

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Verdugo said:
Living in Seattle, where we're at sea level, I thought I didn't have to adjust it at all. However, when I installed mine, the highest I could boost was only 0.88 bar. Granted, it held the boost all the way from spool to redline, but that's only 12.76 psi. I can't explain it, but that's the highest I could boost. Thus, I installed the ABC. Now I'm boosting just about 16 psi and it makes a huge difference.

The ABC shipped with TXS package needs to be installed in order to make proper boost. Even though it ships fully closed, its T-fitting has larger internal diameter than the stock restrictor it replaces, and it allows the boost control solenoid bleed more air (3/16 restrictor mod accomplishes the same thing). Without the ABC, you will always make less boost than stock.
 
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