EBC Settings
#1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I know this has been discussed quite frequently on here already, but has anyone had issues with not being able to tune out the boost overshoot? I have P set super high (170 to 199) and it doesnt seem to help, even with D set high (50 up to 190). I have even tried those high settings with a little and a lot of I, and it all doesnt seem to matter how it reacts. I have a TD04H that is set to target 180 (12psi) in closed loop duty, and it continually shoots way past to 16+psi. Any ideas?
#3
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
its internal. I have thought that maybe the DIYautotune's EBC documentation could be wrong, cause i have checked everything. Funny too, even long 4th gear pulls it will overshoot, but when i am out on I-70 and can open her up with long 5th gear pulls it tends to be more steady, so i dont think it has anything to do with my closed loop map. Sucks too, cause i havent hooked up a TPS, so i have to put all my map values in the 0 TP row across all rpm columns
#10
Boost Czar
![](/mt2011/images_td/ranks/supporter1.gif)
![](/mt2011/images_td/ranks/admin.png)
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,688
Total Cats: 4,113
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
that's closed wastegate DUTY and Open wastegate DUTY.
that's the DUTY cycle of the wastegate. The software requires that the closed value must be lower than open, and since the solenoid at 100%DC would keep the wastegate fully closed, you must select inverted. If the solenoid is at 0%, boost passes through fully and keeps the wastegate open at wastegate levels.
that's the DUTY cycle of the wastegate. The software requires that the closed value must be lower than open, and since the solenoid at 100%DC would keep the wastegate fully closed, you must select inverted. If the solenoid is at 0%, boost passes through fully and keeps the wastegate open at wastegate levels.
#15
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Does this look normal? Sorry, for stealing my thread back. This is the only way i can get close to hitting 12ish and it holding. It still fluctuates a bit from 9 to 12psi up in the 5-6.3K range, but its about as close as i can get it. Any ideas on what could be wrong, or tips on my PID numbers? On my data logs i show the boost duty all over the place going from 0 to 100 every .5 seconds. Doesnt seem right, but its the only way i can get it close to working normally. See attached screenshot for my PID values. I have 180 in every cell above 3500rpm's all the way up and out of my table.
#17
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Just to give some more detail. When i start with 200 for P, and 0's for I and D. I get about 5psi that holds steady. When i start to lower it it will hit 5psi then oscillate (pulse or surge about one psi at a time upwards. When i lower it more it will pulse to a higher final psi. This is when i start adding D, but that high 185 number is the best i could do for it to stop pulsing. That just seems awfully high. The I then finally smoothed it out as best i could. Just doesnt seem solid or correct for that matter.
#19
Boost Czar
![](/mt2011/images_td/ranks/supporter1.gif)
![](/mt2011/images_td/ranks/admin.png)
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,688
Total Cats: 4,113
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
you're not doing it correctly.
Tuning the P term is solely to get to your target, increasing I will hold it to redline.
You should tune P only by spooling the turbo, you shouldn't need ot go any higher than 5000RPM and you should probably just use 2nd or 3rd gear.
Spool up, check peak level. and keep lowering P until you've breeched your boost target. Only then should u move into tuning I, then D.
Tuning the P term is solely to get to your target, increasing I will hold it to redline.
You should tune P only by spooling the turbo, you shouldn't need ot go any higher than 5000RPM and you should probably just use 2nd or 3rd gear.
Spool up, check peak level. and keep lowering P until you've breeched your boost target. Only then should u move into tuning I, then D.
#20
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I have tried that similar approach with quick spools in 2nd gear, but it always overshoots. Its strange that at 200 it will quickly get to 5 then pulse onwards. I would assume this to be the 5psi range equivalent of that P value. Moving P downward yields about the same results, but there is no linear factor (it seems). Suddenly going from 150 to 145 will allow full boost all the way to 15+ before the boost cut kicks in. It will spool quickly to 15+ with a value of 145, but with 150 it shoots to 5 and pulses its way up like it did with the 200 value. Do the closed duty and open duty numbers of 0 and 100 respectively need any tweaking? Just seems very strange.