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" Together with a proportionally controlled dump valve this enables lag mitigation strategies that weren’t possible before." There is no lag mitigation logic in this oem ECU that involves closing the throttle. You plant your foot to the floor, and the throttle blade goes wide open (82%) until you run into a limiter table. The sensor reads up to 30 psi still. We are talking about cars with built motors going for big power. I'm just trying to save you guys money haha. I don't like spending money for no reason, whether it's my car or customer cars. It's also why I tell people not to bother with downpipe upgrades unless they are going to swap the turbo.
 

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" Together with a proportionally controlled dump valve this enables lag mitigation strategies that weren’t possible before” There is no lag mitigation logic in this oem ECU that involves closing the throttle.
Of course there is. Hint: the dump valve bleeds at part throttle. There is a reason for that: the turbo is maintained just below the surge line, the throttle is closed more than normally necessary, the dump valve is cracked open to bleeds the excess pressure and prevent stalling the compressor. All this to keep the turbo spinning faster than it normally would, mitigate the surge that would normally ensue, and control the manifold pressure to deliver the torque requested by the driver, but no more just yet, all while the pre-throttle pressure is kept artificially high.

When the driver depresses the pedal more, the dump valve closes, the throttle opens, whatever extra pressure pre-throttle rushes in instantly, and the turbo is already spinning faster, reducing lag.

This can only be implemented with a PWM dump valve, a DBW throttle, and a TIP sensor in addition to the usual PWM-controlled wastegate.

Many tuners ruin that wonderful strategy by pure ignorance by messing with the throttle area to prevent “throttle closures,” using stiff springs and high preload to “hold boost” and defeating the dump valve control back to “dumb” via a so-called “boost reference adapter.” The WOT pulls sure look good but I don’t know about actual drivability.

When replacing the turbo it is likely very difficult to “remodel” and get everything to work as intended. I replaced the WG capsule and managed to get things to work however I didn’t attempt to replace the turbo yet but I see lots of users asking why their NX2 isn’t making the pressure they hoped or at least not as high-up as it should, and a general confusion about spring rates, preload, and boost control in general, dual port capsules that no one is really sure how to connect, assumptions that the turbo maker ships their engine-specific turbo with the wrong capsule etc.

One thing I completely agree with is that few people really understand the OE PCM and I don’t pretend to be part of them, but the majority of what I see, also through the logs often posted here, is terrible.
 

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The NX2 Turbo
I tried a Tuneplus WGA single port with their secret spring weight. This was only running upto 29psi.

This didn’t hold boost well at all peaking and dropping boost as it felt like and not what it should be doing.

If you get an NX2 turbo the only WGA worth using it the TurboSmart TwinPort Wastegate Actuator it locks the door closed, solid. No flutter or bypass unless it’s actually requested 👍
 
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