OK really...this closed loop boost control is making me furious

Questions about the Platinum Pro Plug-in ECU's? Ask here.
harrisracing
Posts: 39
Joined: Mon Feb 01, 2016 1:58 pm

OK really...this closed loop boost control is making me furious

Postby harrisracing » Wed Mar 01, 2017 2:00 am

I have a pretty sensitive turbo setup. Stroker RB26 GTR...2.75L with Borg Warner 8374 EFR turbo. .92 Internal Wastegate. Now with Turbosmart dual port actuator and MAC 4 port valve.

The problem I am CONTINUALLY having is that when I drag race the car in CLOSED LOOP mode the boost will spike. This is largely due to the 100% bleed of the controller when below the control point before the target boost number. No matter WHAT I set in the PID or anything else, the car will overshoot boost on shifting from 3rd to 4th which causes knock and kills my power. I have the setpoint as the MAX of 7.3 psi before the TARGET number, but is there a way to DELETE this 100% bleed out and make it a smaller number? I say this because this actuator is pretty high on my boost around 30% duty. IF I could keep the low end bleed at 10-20% I am sure I can cure the spike because I can do it in OPEN LOOP mode no problem. Sad thing is CLOSED LOOP nets me 3-400 rpms faster spool to target with a nice low-end smooth pull, but the spike on shift is killing me.

How can I run CLOSED LOOP and lower that 100% bleed duty to a number more reasonable for my setup (that doesn't "Blow down" the actuator between shifts?

moreause
Posts: 29
Joined: Fri May 08, 2015 2:34 am

Re: OK really...this closed loop boost control is making me furious

Postby moreause » Sat Mar 04, 2017 1:23 pm

It's not perfect but that is what i did it remove the boost spike

in my case my WG spring was around 18 psi

Image

the trick to bypass the 100% seem to be asking the current boost pressure when below you spring ..haltech seem's to be thinking he's already a desired boost

Image

you can aslo this kinda of table in open loop in summer for me was working fine

you would asjust duty by psi like 25% from 0 to setpoint and 20% from setpoint and over knowing 20% would give you to low psi

so haltech try to reach an equilbrium between 25 and 20% that give the right psi

like overhere

Image

in this exemple it would setle around 22/23 psi

cux350z
Posts: 25
Joined: Mon Mar 28, 2011 6:06 am

Re: OK really...this closed loop boost control is making me furious

Postby cux350z » Sun Jun 11, 2017 9:10 am

Lets be honest...haltech has done a horrible job explaining and programming their closed loop boost controller.

I posted years back asking for an explanation....probably linked to a video or crickets with no resolve.

In my opinion the BC should beat 100% closed, Haltech should ask what the WG spring is, target boost level and estimated duty cycle and then PID values. After that...it should work.

From what I can see, you have to build your tables to ramp the boost in below the WG spring. Meaning, if you know you spool to wg by 3500rpm, set the table up to get the BC working by then.

User avatar
HaltechMatthew
Haltech Staff
Posts: 2578
Joined: Tue Feb 07, 2012 12:45 pm
Location: Sydney, Australia
Contact:

Re: OK really...this closed loop boost control is making me furious

Postby HaltechMatthew » Thu Jun 15, 2017 2:39 pm

For the Pro range the 100% spool assist cannot be turned off. Annoying I know, and it is something they added the ability to do with the Elites but not the Pro. Open loop only is the only option.

NISMORIC
Posts: 11
Joined: Sat Jun 06, 2015 4:50 am

Re: OK really...this closed loop boost control is making me furious

Postby NISMORIC » Fri Dec 29, 2017 8:59 pm

This explains a lot! I was chasing this issue for a while, during ramp runs of 3-8k closed loop boost control worked well but during gear changes I would always overshoot the target.

with that being said, since open loop only is being recommended would it be possible to hookup an ambient temp sensor to feed information to the ecu in an effort to control boost during temp changes?

User avatar
HaltechMatthew
Haltech Staff
Posts: 2578
Joined: Tue Feb 07, 2012 12:45 pm
Location: Sydney, Australia
Contact:

Re: OK really...this closed loop boost control is making me furious

Postby HaltechMatthew » Fri Jan 05, 2018 11:51 am

Certainly. You can map it against anything you like!


Return to “Platinum Pro Plug-in”

Who is online

Users browsing this forum: No registered users and 3 guests