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Also, wouldnt the turbo speed calculation be pretty accurate regardless of wastegate function? They know the inlet pressure of the turbo from the sensor after the air box, they know the MAP and the TIP, they know the temperatures, and they can figure out the mass air flow pretty accurately via the O2 sensors and VE equations.

Thats all you should need to be able to plot it on the compressor map.
 

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I'm sure the PCM knows pretty accurately the compressor speed considering ford has extremely intelligent engineers that worked hand it hand with the manufacturer of the PCM and turbo. I'm just not sure personally how to calculate that. Maybe someone with better mathematical skills could help us out with that. Most times I would just check the compressor MAP, but it seems that data will never be published for our turbos.

The way I think about it is this. If your wastegate opens and the duty cycle is 100% (trying all it can to close), then you are correct, you are not getting the full amount of boost because the exhaust energy is being wasted, though the wastegate is not trying to do that. So energy that would normally create more boost is being evacuated. On top of that, the turbo could be overspeeding still, especially for those of you at higher altitudes.

This would be especially prevalent at higher elevations where the air is less dense and thus the turbo already has to work harder to maintain target. I think for the most part, sea level guys are not going to see this issue. I have personally run 22 psi and then some on stock turbos, though I do not know if the wastegate was opening. I assume not as my duty cycle was not 100% (going by memory).

I can see how the WORM gear would be concerning if it were to stop working, however there is a check at every key cycle for functionality of the E-wastegate. If it were to be stuck, dead, or broken, the PCM would likely put the truck in FMEM (failure mode effects management) to keep the engine safe. There would also be a CEL etc to follow. Honestly its probably safer than the older style because the PCM really doesnt know what the wastegate is doing on the older system, it just knows what the solenoid is trying to do and the result of that (boost). Hence the overboost/underboost controls in the PCM as well.

Also consider these types of e-wastegates are likely adapted from something that has been used in automotive for a long time. Possibly an adapted electronic throttle body motor, evap, egr or other, where a valve is generally controlled. So these will likely be very reliable.

And as @Fstrnyou stated, the opening of the wastegate if from pre-turbo backpressure, not after the turbo. So this is the area coming directly off the manifold and over the exhaust turbine. The air exits past the turbine and/or through the wastegate and then goes through your downpipe. Backpressure in this case (post turbo) would actually help keep the wastegate shut as there is pressure on both sides of the wall (wastegate) so-to-speak.

Its like a door, if pressure is put on it, it can open. If you put pressure on both sides that is equal, it will not move. Pressure differential and surface area, and other math things.
 

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I'm sure the PCM knows pretty accurately the compressor speed considering ford has extremely intelligent engineers that worked hand it hand with the manufacturer of the PCM and turbo. I'm just not sure personally how to calculate that. Maybe someone with better mathematical skills could help us out with that. Most times I would just check the compressor MAP, but it seems that data will never be published for our turbos.

The way I think about it is this. If your wastegate opens and the duty cycle is 100% (trying all it can to close), then you are correct, you are not getting the full amount of boost because the exhaust energy is being wasted, though the wastegate is not trying to do that. So energy that would normally create more boost is being evacuated. On top of that, the turbo could be overspeeding still, especially for those of you at higher altitudes.

This would be especially prevalent at higher elevations where the air is less dense and thus the turbo already has to work harder to maintain target. I think for the most part, sea level guys are not going to see this issue. I have personally run 22 psi and then some on stock turbos, though I do not know if the wastegate was opening. I assume not as my duty cycle was not 100% (going by memory).

I can see how the WORM gear would be concerning if it were to stop working, however there is a check at every key cycle for functionality of the E-wastegate. If it were to be stuck, dead, or broken, the PCM would likely put the truck in FMEM (failure mode effects management) to keep the engine safe. There would also be a CEL etc to follow. Honestly its probably safer than the older style because the PCM really doesnt know what the wastegate is doing on the older system, it just knows what the solenoid is trying to do and the result of that (boost). Hence the overboost/underboost controls in the PCM as well.

Also consider these types of e-wastegates are likely adapted from something that has been used in automotive for a long time. Possibly an adapted electronic throttle body motor, evap, egr or other, where a valve is generally controlled. So these will likely be very reliable.

And as @Fstrnyou stated, the opening of the wastegate if from pre-turbo backpressure, not after the turbo. So this is the area coming directly off the manifold and over the exhaust turbine. The air exits past the turbine and/or through the wastegate and then goes through your downpipe. Backpressure in this case (post turbo) would actually help keep the wastegate shut as there is pressure on both sides of the wall (wastegate) so-to-speak.

Its like a door, if pressure is put on it, it can open. If you put pressure on both sides that is equal, it will not move. Pressure differential and surface area, and other math things.
The 2017+ actuator tech is probably related to the diesels. Garrett has been using electric actuators on their VNT turbos since the early/mid 2000's. Now practically every diesel turbo is electrically actuated.

On the diesel actuators, I believe they have a failsafe that will fail them open, IE, open the vanes so the turbo doesnt make boost.
 
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