PI controller pro's & Con's comparison: JB4 PI vs split 6

[Terry@BMS]

We used to have a "reset to defaults" option. Was a total disaster. People run interface versions that are out of date and reload the wrong options, they add parts that suddenly default don't apply to and wonder why its not working, etc. It was worse than what we did now which was why we removed those and simply post the settings in the specific thread. Which largely works very well. I'd love to come up with some sort of an interface wizard that makes setup easier but it's already pretty easy. One of the strengths of the JB4 implemnentation is how flexible it is and with that will come some confusion

This AFR rich thing isn't an issue of default settings being wrong. He has a custom tuner working with him. The tuning does whatever the tuner tells it to do. The settings look reasonable other than when on PI and a BEF you set open loop to 0 which may have prevented AFR from going so rich. That said I don't think his tuner expected a 10:1 AFR short run to blow a motor.

The concern I have is if we know 10:1 AFR is likely to damage a motor then let's just failsafe on a 10:1 AFR. The real key to the JB4's success is the passive safety systems that go above and beyond what can be easily done flash only. It took me less time to add the 10:1 AFR safety logic than it did to write this reply. My general question to those of you who are tuners or do tuning, do you ever run or plan to run really rich tuning? If so we'll need a "disable" option for the safety.

 

[bahn]

I’ve made my engine blown because of PI. Terry , my tuner didn’t tell me to set fuel bias to 20 , did also not to set FOL to zero , and run in map 1 to verify the things , and he didn’t make me remind that fuel bias settings are applied in all maps. So once I went to the high way to do a log and evaluate the things , I was in map 1 and fuel bias settings were set in 75 and FOL was in 40. The car took an immediate action and misfire cylinder 1 code popped up and never gone. Once we opened the engine , we saw that all cylinders walls were washed and crappy with scratches. Can’t you take any precautions for such situations , I think Jb4 should not let the fuel bias settings apply in all maps

What index were the injectors?

 

[cebrailbakan]

What index were the injectors?

#12

 

[Vdkk]

In for info

 

[luchocamp]

JB4 is great equipment. No benefit from AFR under 10.8 maybe failsafe to map 4 after that.

 

[BreakMyBillfold]

With our off the shelf stuff on single turbo, the suggested JB4 PI values of 80, off the shelf E85_PI BEF, open loop set to 0, trims are generally very level and fuel pressure is maintained.

Terry, what is the hybrid turbos (Pure Stage 2 Hi-Flow, specifically) version of this BMS PI values summary? I'm using the off the shelf E85 PI BEF, and realized I don't have the correct starting values, such as FOL=0.

 

[Terry@BMS]

Terry, what is the hybrid turbos (Pure Stage 2 Hi-Flow, specifically) version of this BMS PI values summary? I'm using the off the shelf E85 PI BEF, and realized I don't have the correct starting values, such as FOL=0.

It's easy, just set "fuel bias" all to 50 in the JB4 user adjustment page, load the E85 PI BEF, and you're off and running. IF you need any help just capture a JB4 log and post it to the n54tech support forum or email it in and we can ensure it's working right, provide tuning advice.

 

[Maniac0908]

Ok, April 2019. I’m going single. Getting the precision raceworks pi, and making my own stage 3 LPFP. (Maybe stage 4 if I have the funds). What’s the best set up controller wise? I have jb4 with a custom bef. Should I use jb4 pi controller or spilt second? Do I need jobs switch? Does jb4 pi controller have the high power wire now so we can also have 2step? Thanns

 

[Payam@BMS]

Ok, April 2019. I’m going single. Getting the precision raceworks pi, and making my own stage 3 LPFP. (Maybe stage 4 if I have the funds). What’s the best set up controller wise? I have jb4 with a custom bef. Should I use jb4 pi controller or spilt second? Do I need jobs switch? Does jb4 pi controller have the high power wire now so we can also have 2step? Thanns

JB4 PI controller for sure. Everything is integrated into one, no need for a hobbs switch. The PI controller has a trigger for the secondary fuel pump.
Yes, you can use 2step as always.

 

[Max]

@ Terry

Hi Terry, this discussion ist quite old, but I´ve one question on the log from [U]cebrailbakan[/U]. After a few seconds logging the trim value is going to 0. I have made a lot of loggings, but never had trims of 0. Do you have an idea?

 

[Payam@BMS]

@ Terry

Hi Terry, this discussion ist quite old, but I´ve one question on the log from [U]cebrailbakan[/U]. After a few seconds logging the trim value is going to 0. I have made a lot of loggings, but never had trims of 0. Do you have an idea?

Are you using the JB4 PI controller? If so, do you have a log so I can take a look?
More than likely you'll have to set open loop to 0 and lower your fuel bias settings.

 

[Max]

Are you using the JB4 PI controller? If so, do you have a log so I can take a look?
More than likely you'll have to set open loop to 0 and lower your fuel bias settings.

No, I‘m not using it, sorry. Behause I try to understand the JB4 as good as possible, I‘m interested how the trim value can be zero.

 

[Payam@BMS]

No, I‘m not using it, sorry. Behause I try to understand the JB4 as good as possible, I‘m interested how the trim value can be zero.

It's hard to identify without a log. I'd send one to your tuner and see what he says. More than likely you'll have to remap your AIC 6 PI controller if it's dumping too much fuel.