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Kingtal0n · 08-10-2021, 09:58 AM

^^ good post

I just want to add some things

1. The vacuum line on the back of the controller is absolutely ESSENTIAL that it be a single, large, dedicated line that runs to the intake manifold. Do not T' it off to anything else and make sure the hose diameter is as large as the port on the back of the controller, and that this line is as short as possible.

2. This boost controller is an open loop controller, it has no feedback. It does not monitor your engine. It it not a PID controller, only P proportional gain as a duty cycle and amplitude output.

3. The solenoid greddy supplies is a 3-port solenoid generally capable of approx 50% duty cycle max usage. Anything over 50% duty on a typical 3-port will generally lead to poor control, oscillations or outright failure to respond.

4. How to use these controllers
A. Set the "start" function to zero so it does nothing
B. Set the duty cycle to 0% and gain to 10 or 15% so the controller is essentially "OFF"
B2. Make sure the warning is set higher than the max boost you intend to run so it doesn't trigger.
C. Now run the car at wot and see what your boost pressure is with the controller OFF. It should be nearly identical to when the controller is disconnected completely.

Now, begin turning up the duty cycle.
D. gradually increment duty cycle 10%, 15%, 20%, etc... until desired target boost is reached.

Now, fine tuning:
E. Begin turning up the "start" feature to delay the onset of wastegate cracking open. This will cause a "RUSH" to the target boost. It is OKAY to set the START boost higher than your target boost pressure. You may also wish to experiment with using more GAIN as it may further increase the rush and overshoot of boost target if desired.

For example, Lets say my duty cycle is 25% and my boost pressure is 15psi of boost.
If I set my "start" feature to 16psi, the boost pressure will Rapidly rise to 16psi (or slightly higher) then fall back to 15psi, giving the vehicle a sudden burst/onset of torque which may or may not be useful or desirable.

for a smoother onset of boost, set the "start" feature to a much lower boost pressure than your target so the gate can crack open sooner.

08-10-2021, 09:58 AM	#3
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 41 Posts: 4,828 Trader Rating: (17)	^^ good post I just want to add some things 1. The vacuum line on the back of the controller is absolutely ESSENTIAL that it be a single, large, dedicated line that runs to the intake manifold. Do not T' it off to anything else and make sure the hose diameter is as large as the port on the back of the controller, and that this line is as short as possible. 2. This boost controller is an open loop controller, it has no feedback. It does not monitor your engine. It it not a PID controller, only P proportional gain as a duty cycle and amplitude output. 3. The solenoid greddy supplies is a 3-port solenoid generally capable of approx 50% duty cycle max usage. Anything over 50% duty on a typical 3-port will generally lead to poor control, oscillations or outright failure to respond. 4. How to use these controllers A. Set the "start" function to zero so it does nothing B. Set the duty cycle to 0% and gain to 10 or 15% so the controller is essentially "OFF" B2. Make sure the warning is set higher than the max boost you intend to run so it doesn't trigger. C. Now run the car at wot and see what your boost pressure is with the controller OFF. It should be nearly identical to when the controller is disconnected completely. Now, begin turning up the duty cycle. D. gradually increment duty cycle 10%, 15%, 20%, etc... until desired target boost is reached. Now, fine tuning: E. Begin turning up the "start" feature to delay the onset of wastegate cracking open. This will cause a "RUSH" to the target boost. It is OKAY to set the START boost higher than your target boost pressure. You may also wish to experiment with using more GAIN as it may further increase the rush and overshoot of boost target if desired. For example, Lets say my duty cycle is 25% and my boost pressure is 15psi of boost. If I set my "start" feature to 16psi, the boost pressure will Rapidly rise to 16psi (or slightly higher) then fall back to 15psi, giving the vehicle a sudden burst/onset of torque which may or may not be useful or desirable. for a smoother onset of boost, set the "start" feature to a much lower boost pressure than your target so the gate can crack open sooner.