Ecu gn boost controld

[js402]

I'm looking to use the boost control feature on the ecu gn and am curious as to what all is needed to make it work. I've got a precision external gate and a 4 port mac valve already. I know that the mac ties in on the factory solenoid. Do I need a pressure sensor on the wastegate and if so, where would I tie that to?

 

[BEATAV8]

A pressure sensor would be used for dome control.
If you’re just getting started you should try simple open loop control. That’s where the boost duty map just sends a duty cycle to the mac valve to control boost level.
From there you can graduate to closed loop boost control which is more complicated.

3 port valve is good for most applications

4 port valve can be used when you need a very wide range of control. Flex fuel for example, running 15psi on gas and 34psi on ethanol letting the ECU slew between them automatically. This also makes the system very sensitive to small changes in duty

 

[js402]

Ok so without a pressure sensor at the wastegate, is the ecu just going to use kpa from the map for boost pressure?

 

[BEATAV8]

For open loop control it won’t even look at boost (map), it will look at RPM and TPS and it will spit out a duty cycle for the mac valve.

When you upgrade to closed loop control is when it will look at MAP and try to control to it. Before you move to closed loop you should have a good understanding of how much boost you get when you send a certain duty cycle. You’ll need that to populate the boost duty bias table. It’s like a feed forward, it tells the computer how much duty to send in order to achieve the desired boost target as close as possible. Then the closed loop kicks in to fine trim the duty to try and achieve the target

 

[BEATAV8]

Ok so without a pressure sensor at the wastegate, is the ecu just going to use kpa from the map for boost pressure?

Yes