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I reciently got my hands on a RB20DET actuator for my r33 gtst as I beleived there spring is rated at 10psi (R33 is 6psi).

Before installing it on my car I tested it with an air compressor in conjunction with a boost gauge and all seemed fine started to open at 10psi.

Took my old one off and did the same test it started to open at 6psi. So I installed the RB20DET actuator but I had to bend the arm in order to get it arround the turbo. After doing this I used the air compressor again and it started to open at 10psi perfect.

But when I test drove the car boost would only hold to 5psi wich is were my probem lies. I put a thread on the actuator arm to adjust the tention after many trials the best we could manage was 8psi to 5000 and then it creeps up to 11psi to 7000 whch does not give the wastegate much room to move as the rod is so short.

Does any body know what might be wrong? Ive heard that many people have had great success with this mod.

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Bear in mind, i do believe, the factory ecu controls boost and adds a few psi in the last 2000rpm of the rev range, do you still have the vacum hoses plugged into a solenoid near the power steering fluid resivoir on the passenger side strurt housing?

Bear in mind, i do believe, the factory ecu controls boost and adds a few psi in the last 2000rpm of the rev range,  do you still have the vacum hoses plugged into a solenoid near the power steering fluid resivoir  on the passenger side strurt housing?

Yes im sure I have it connected right. But just in case heres a pic

Yeah if its still plugged in budy the factory ecu will still be in control of boost, giving you that raise in boost at the end of the rev range. Why your getting less than 10psi on a 10psi actuater spring is beyond me. Are you measuring boost in your car at the manifold? Remember by the time boost passes through intercooler, etc you will lose a few psi. Other than that im not real sure mate.

Yeah if its still plugged in budy the factory ecu will still be in control of  boost, giving you that raise in boost at the end of the rev range.  Why your getting less than 10psi on a 10psi actuater spring is beyond me.  Are you measuring boost in your car at the manifold? Remember by the time boost passes through intercooler, etc you will lose a few psi. Other than that im not real sure mate.

Yes I am messuring boost from after the intercooler so I dont know whats going on.

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