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Now then -- you decide to install boost jets into the boost signal line while keeping the stock solenoids installed. You put in .045 jets and are now running 14 psi. The boost jet is restricting the actual boost signal, "tricking" the system and showing the actuator less pressure (boost) than actual boost. The small hole in the boost jet allows less pressure through the signal hose (about 4-5 psi in this case). The factory solenoid further bleeds this signal (about 3 psi). The result is that the actuator sees 6 psi of pressure when in actually you are running 14 psi into the manifold. Another issue here, the signal is bleeding to the actuator as boost increases. So, when you're at 10 psi, the actuator sees 2 psi. When at 12, actuator sees 4 psi. The actuator may actually start moving once pressure is getting close the operating opening pressure, as in the stock setup (discussed above).
Another issue with boost jets, also seen in the stock setup (but not as serious), is boost spike. The boost level seen in the engine can spike for brief moments before the actuator operation opens the wastegate and holds boost at max. This can be dangerous for the engine, leading to pre-detonation.
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