Need help understanding EBC...
#1
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Hi Guys
As you will undoubtedly have noticed I am struggling through the noobie stages of setting up my rev built enhanced MS2.
From another thread I believe my race day issues were likely caused by ovrerboost control issues/settings. I have left all of these at the Reverant Default values....
Don't get me wrong, I am not averse to reading, studying and learning by myself. The problem is there is SO much different information through various versions of megasquirt, different forums and of course the obtuse nature of replies here at MT (not to mention terrible searching/ too many results) figuring this stuff out is hard bloody work.
For example, there is a sticky above in this thread about EBC for MS1/PNP that I have no idea if it is applicable or not....
So would someone mind putting some links in for me to reference KNOWING I will not be looking at the wrong or outdated thing...?
Or if anyone has a moment to explain I would very much appreciate it.....
To clarify, I have a Reverent built Enhanced MS2 with a default 1600 turbo base map.
I want the option to run at 7 (wastegate), 10,12 and 14 PSI boost depending on the track/weather conditions......and am happy to do fuel tuning / VE analyse etc for each one but just don't know what numbers to change within the boost control area, what to look out for etc.....
As you will undoubtedly have noticed I am struggling through the noobie stages of setting up my rev built enhanced MS2.
From another thread I believe my race day issues were likely caused by ovrerboost control issues/settings. I have left all of these at the Reverant Default values....
Don't get me wrong, I am not averse to reading, studying and learning by myself. The problem is there is SO much different information through various versions of megasquirt, different forums and of course the obtuse nature of replies here at MT (not to mention terrible searching/ too many results) figuring this stuff out is hard bloody work.
For example, there is a sticky above in this thread about EBC for MS1/PNP that I have no idea if it is applicable or not....
So would someone mind putting some links in for me to reference KNOWING I will not be looking at the wrong or outdated thing...?
Or if anyone has a moment to explain I would very much appreciate it.....
To clarify, I have a Reverent built Enhanced MS2 with a default 1600 turbo base map.
I want the option to run at 7 (wastegate), 10,12 and 14 PSI boost depending on the track/weather conditions......and am happy to do fuel tuning / VE analyse etc for each one but just don't know what numbers to change within the boost control area, what to look out for etc.....
#2
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You're not going to manage all those options.
You can run a switch in-line to turn off your EBC so you can have say wastegate, and 14 psi. but that's it. there's only one boost target table with MS2, (
MS3 has boost control table switching), so there's no way of switching targets that I know of.
I know Rev has built in additional features over and above a 'normal' MS2, so it may be that you'll be able do something with his ECU.
You can run a switch in-line to turn off your EBC so you can have say wastegate, and 14 psi. but that's it. there's only one boost target table with MS2, (
MS3 has boost control table switching), so there's no way of switching targets that I know of.
I know Rev has built in additional features over and above a 'normal' MS2, so it may be that you'll be able do something with his ECU.
#6
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Sorry, that was a bit vague, with this ECU I can run two boost maps and switch between probably 12-14 (to be decided) and 8 (8 for wet weather) but thats not my point.
I want to work towards each target boost as listed BUT don't know what numbers to change in the tunerstudio software...to get away from wastegate controlled boost......my boost control settings say Open Loop and EBC map says 100 in every column...what the hell does that mean..?
I changed it to 85 as a test and had no change in boost levels.....
My hesitation durign the last race meeting has been described as overboost protection, how do I adjust that. I have found plenty of material about what it does but not how and where to adjust it...
So some of my research last night found this ifno in the MS2 PNP Gen 2 manual....
this is the sort of info I am asking for help with....I know the source material title (MSPNP Gen2) may be inaccurate but the tunerstudio s/w used is the same so it is the same process/info for me as listed above right?
If that is the case, is there any way to know what the values are? or ballpark values I need for 10 psi or is this specific to each engine/turbo and relies purely on trial and error...?
I really want to move away from wastegate pressure (7psi) to 10 Psi but obviousley need to understand this all first.
Also, I don't see reference to PSI in tunerstudio am I best to start learning and working in KPA or does it not matter because perhaps tuner studio works in duty cycles only...?
Perhaps seeing someones duty cycle and what sort of boost it gets them would put this in perspective for me..?
I want to work towards each target boost as listed BUT don't know what numbers to change in the tunerstudio software...to get away from wastegate controlled boost......my boost control settings say Open Loop and EBC map says 100 in every column...what the hell does that mean..?
I changed it to 85 as a test and had no change in boost levels.....
My hesitation durign the last race meeting has been described as overboost protection, how do I adjust that. I have found plenty of material about what it does but not how and where to adjust it...
So some of my research last night found this ifno in the MS2 PNP Gen 2 manual....
Boost Control
The MSPNP has an electronic boost control feature supporting open and closed loop boost control. Once you have wired this up, you can enable boost control in TunerStudio. In open loop mode, the boost control solenoid puts out a signal at a fixed duty cycle (that is, a percentage of time the solenoid is open) as a function of RPM and the throttle position sensor. This is a bit easier to tune and will generally keep the boost right where you set it, but can drift a psi or two with dramatic changes in air temperature and other variables. You'd be most likely to notice this if for instance you had tuned the car on a 80degF day for 15psi of boost, then drove it on the 32degF day. In that case you might see an extra pound or two of boost. Closed loop boost control is a bit more complicated to tune, but when properly setup allows the ECU target and correct to a specific boost pressure regardless of ambient air temps and other variables that come into play.
NOTE-- while many EBC valves could be used, we recommend using the EBC solenoid available from DIYAutoTune.com. This is the valve we have tested with, and have setup the base maps to support by default.
When running boost control, you'll set up the basic parameters for the valve under the Boost Control screen in the Advanced menu. For our EBC solenoid, we recommend a frequency of 19.5 Hz and a control interval of 20 ms. The boost control pin is always PA0. The Output Polarity setting is Normal. The duty cycles can be a little confusing at first glance: They refer to waste gate opening, not solenoid opening. Set fully closed to 100% duty cycle (this means an open valve applying maximum pressure to the waste gate) and fully open to 0% duty cycle (a closed valve will send no pressure to the waste gate).
The MSPNP has an electronic boost control feature supporting open and closed loop boost control. Once you have wired this up, you can enable boost control in TunerStudio. In open loop mode, the boost control solenoid puts out a signal at a fixed duty cycle (that is, a percentage of time the solenoid is open) as a function of RPM and the throttle position sensor. This is a bit easier to tune and will generally keep the boost right where you set it, but can drift a psi or two with dramatic changes in air temperature and other variables. You'd be most likely to notice this if for instance you had tuned the car on a 80degF day for 15psi of boost, then drove it on the 32degF day. In that case you might see an extra pound or two of boost. Closed loop boost control is a bit more complicated to tune, but when properly setup allows the ECU target and correct to a specific boost pressure regardless of ambient air temps and other variables that come into play.
NOTE-- while many EBC valves could be used, we recommend using the EBC solenoid available from DIYAutoTune.com. This is the valve we have tested with, and have setup the base maps to support by default.
When running boost control, you'll set up the basic parameters for the valve under the Boost Control screen in the Advanced menu. For our EBC solenoid, we recommend a frequency of 19.5 Hz and a control interval of 20 ms. The boost control pin is always PA0. The Output Polarity setting is Normal. The duty cycles can be a little confusing at first glance: They refer to waste gate opening, not solenoid opening. Set fully closed to 100% duty cycle (this means an open valve applying maximum pressure to the waste gate) and fully open to 0% duty cycle (a closed valve will send no pressure to the waste gate).
If that is the case, is there any way to know what the values are? or ballpark values I need for 10 psi or is this specific to each engine/turbo and relies purely on trial and error...?
I really want to move away from wastegate pressure (7psi) to 10 Psi but obviousley need to understand this all first.
Also, I don't see reference to PSI in tunerstudio am I best to start learning and working in KPA or does it not matter because perhaps tuner studio works in duty cycles only...?
Perhaps seeing someones duty cycle and what sort of boost it gets them would put this in perspective for me..?
Last edited by mx5-kiwi; 09-13-2013 at 03:08 PM.
#7
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Start reducing the values in the map from 100 to lower values. The lower the values, the higher the boost. There's no way of predicting how much you need to lower to achieve the target you boost. Just keep reducing until you get there. In most cases, a value between 50 and 75 will get you there, however I always recommend taking it easy and please have a sensible overboost limit dialed in just in case.
#8
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Perfect thank you!!!
I can't seem to find the overboost section in the s/w, where is this?
edit :
Okay found it.
so this is a concern...
Max Boost (Low) (KPa) 185
Hysteresis (Low)(KPa) 10.0
Maximum Boost (High)(KPa) 200
Hysteresis(High)(KPa) 10.0
My boost guage is showing only 7 psi and the wastegate itself is only a 7 psi one.
seeing as 7 psi is only 48 KPa, there is no way these figures should be allowing the boost cut to be the problem....IF (a big IF) I am getting a grasp on things?
I can't seem to find the overboost section in the s/w, where is this?
edit :
Okay found it.
so this is a concern...
Max Boost (Low) (KPa) 185
Hysteresis (Low)(KPa) 10.0
Maximum Boost (High)(KPa) 200
Hysteresis(High)(KPa) 10.0
My boost guage is showing only 7 psi and the wastegate itself is only a 7 psi one.
seeing as 7 psi is only 48 KPa, there is no way these figures should be allowing the boost cut to be the problem....IF (a big IF) I am getting a grasp on things?
Last edited by mx5-kiwi; 09-13-2013 at 04:16 PM.
#9
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Your grasp definitely still seems week in one area: 7psi boost is 48kpa PLUS outside pressure. Near sea-level outside pressure is approx. 100kpa, so 7psi boost is 148kpa.
Not even close to 185 though.
What does your map sensor show when it cuts out?
On open loop EBC tuning: I had to drop my values from 100% to about 60% to start seeing effects.
Not even close to 185 though.
What does your map sensor show when it cuts out?
On open loop EBC tuning: I had to drop my values from 100% to about 60% to start seeing effects.
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