Author Topic: Boost control setup help  (Read 12493 times)

Offline JohnP

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Boost control setup help
« on: March 14, 2018, 11:35:09 pm »
I am ready to begin the installation of my boost contron solenoid. I have a V3 board an running 1.1.96. I currently have 9lb springs in the wastegate and targeting 15psi to start. I am running a S480 with a 1.10 housing and need the boost controllers help to increase spool instead of gate early cracking.

Is anyone willing to share a screenshot of values needed to hit my target?  I am unable to see gunnis write up.

Thank you
 John P
« Last Edit: March 16, 2018, 12:27:48 am by JohnP »

Offline jrussell

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Re: Boost control setup help
« Reply #1 on: March 15, 2018, 12:16:02 am »
You don't explain why you're "splice the tps 5v reference wire" and I can't think of a good reason to do that. Can you elaborate?

Wire the boost solenoid to +12v (through a fuse, please!) and the second terminal to one of the high power outputs of the ECU (injector or coil are the best) and chose the output in "Outputs -> Assign Output Channels" Boost Control Channel entry.

In the Boost PID Settings, set Boost P, I, and D all to 0. Set Boost pwm max value to 95 or so. Boost pwm min value to 0. Check the help file (Press F1) if you want to know details of any of the settings.

Then set your Boost vs. RPM Curve as you wish your boost to be like.

Then set your refDC vs. Boost Target to get close to your RPM/Boost curves. Higher DC = higher boost. Try starting with around 20-30% and see where that puts you. Increase if it's lower than desired, decrease if boost is too high. Rinse and repeat. Once you have your base refDC pretty well sorted, you can go back and turn on PID if you wish to give you closed loop boost control.


If you don't ever want closed loop, you can use boost alternate, which is easier to set up, but open loop only. Just throwing it out there as an option. Boost control is really hard to explain without going into crazy amounts of detail. This should get you on the right track though.

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Offline JohnP

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Re: Boost control setup help
« Reply #2 on: March 16, 2018, 12:31:52 am »
Excellent. Thank you. I was mixed up on 5v as to monitor fuel pressure (different project) . I will have it 12v fused. I am aiming to get the turbo to respond better and be able to use launch control with lower target boost settings.

Offline JohnP

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Re: Boost control setup help
« Reply #3 on: March 22, 2018, 02:27:29 am »
I have read to use igbt outputs or injector outputs. Not to use p259. Im seeing i259 and s259 but do not see these labeled on my v3.6 pin out sheet. Can someone elaborate. Is i259 the ignition outputs? I have 10,11,12, and 24 available of that is correct.

Lastly using a mac 3 port boost solenoid. I read to interrupt the signal to the bottom of my dial port wastegate. Is there no other way to plumb it with vems?
« Last Edit: March 22, 2018, 03:32:10 am by JohnP »

Offline jrussell

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Re: Boost control setup help
« Reply #4 on: March 23, 2018, 06:48:49 pm »
i259 is the ignition driver, so yes, those map out to ignition outputs.

Regarding the boost solenoid plumbing, that's not VEMS specific, and there are many ways to plumb it. My personal favorite is how you explained it. And plumb the valve so if it's off, the wastegate gets full pressure from the manifold/turbo. That way a failure leads to low boost not infinite boost.  ;)
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