That is a misunderstanding.
With the duty cycle at zero, boost pressure will be minimized.
If you disconnect the wastegate solenoid valve (the equivalent of 0% duty cycle), the boost pressure would be limited to ~10 PSI (assuming no mods).
That is also a misunderstanding.
The high duty cycle (the OP's log has a max. of >99%) shows that the ECU has "cranked up the boost to the max" by closing the wastegate as much as it can (it cannot close the wastegate completely). It makes perfect sense considering 17.5 PSI @ ~6000 RPM with a small turbo.
Bravnik made the incorrect assumption that "Wastegate duty %" was referring to the actual wastegate opening. Should I have not said anything?
Ok, I'm not sure what crack you are smoking, but that is not how a WG works bro. Here is the definition of a WG and what it does.
"The wastegate (WG) is part of a feedback loop used to limit boost. The boost controller, be it manual or electronic, the turbo, and the wastegate make up the elements of the loop. As boost builds, the controller monitors the pressure. When the pressure exceeds the controller's set point, it supplies air pressure to the WG actuator (the thing that moves the WG). The WG opens and diverts some of the exhaust flow away from the turbo. The turbo slows a little and the boost drops to below the controller's set point. When this happens, the controller stops supplying air to the actuator and the WG closes. The cycle repeats over and over until you stop nailing the accelerator!
How much the boost varies about the set point is a function of the "gain" of the loop and how much it is "dampened." It's more than you probably want to know.
There is a spring in the WG actuator that has a lot to do with how well the WG remains closed while boost builds. The WG actuator has to overcome the spring force to open the WG. The exhaust gas pressure isn't very significant so the actuator has to do most of the work. The spring force has an affect on the "gain" of the loop, so it can affect the loop response time.
Small turbos imply low boost levels so they are able to employ internal WGs. A small turbo running high boost levels (not recommended since turbo efficiency falls off dramatically) can overwhelm its WG and boost creep will result (the gate can't open enough to divert the huge amounts of exhaust gasses away from the turbo). External WGs are often larger and can more effectively divert larger amounts of exhaust gasses away from the turbo when they open.
Boost creep is what happens when the boost climbs beyond the set point limit established by the controller. Boost creep is caused by the inability of the WG to divert enough exhaust gas away from the turbo. There are several reasons this can happen but the cheap solution is to lower the set point!
WG designers expected a significant pressure difference on either side of the WG valve. It is required so the gasses rush through the valve when it opens. If the pressures on both sides of the WG are equal, nothing happens when the WG opens (so no boost regulation can happen). What can make the pressures equal? A restrictive exhaust system!"
Unless I'm TOTALLY misunderstanding your point, you need to do a bit of reading before you come into a forum and tell people they are wrong friend.
So again 0% is a CLOSED WG = Boost can build as it is not being bled off. 99% WG is a completely open WG allowing exhaust gases to bleed off thus slowing the turbo THUS lowering boost. I was not mistaken or wrong in my statement at all. Hell the simplest way to verify this is look at the WG table in the AP log. When he is not in boost the WG is at 0%. If your theory was valid then he should be at 20PSI at that point!
Our WG spring is set to 10PSI. If you disconnect the factory Boost Controller then you run WG only and the max PSI you will see is 10PSI. Maybe you are confusing the Boost Controller with the WG. That is the ONLY explanation for your comments as you are 100% wrong on what you think a WG does. A simple 5 second Google on "How does a wastegate controller work" will (or should) prove this to you or anyone else.
Actually I see where your confused. What you are calling a WasteGate Solenoid is actually a Boost Controller Solenoid. When the boost pressure setting is reached (15.6 psi stock), the Solenoid activates the WG Actuator and OPENS the WG to lower boost. However you are still very wrong in saying that 0% is FULL BOOST and 99% is Closed making less boost. Sorry man.
