[Phdv61]

Point taken and understood.
But let me disagree.
IF I reduce the MAF voltage by 0.3V (I used to do that in the past to kill limp), I loose a lot of power /Torque.
Since the ECM adds fuel wrt MAF voltage ( quantity of air), the equation less air + less fuel = less power was explainable.
I have therefore difficulties to follow you when you say MAF voltage is not that important, and that I would not see any difference on a dyno.
I am using no remap, the stock fuel table and AFR.
I can drive up in steep mountains in 5th gear whilst in the past I had to go 4. There must be a difference therefore.
And everybody running an MB have shared the same positive experience.

Why would engineers design a clever vanes system for turbo to adjust the flow if a two stage turbo ( vanes fully closed or fully open ) provide the same result. Hard to believe. I can't follow you on that one.

What is sure is that as long as you keep the vanes aroiund 1/2 open ( or 1/2 close) more or less, it is the area where the VNT is the most efficient. Valves do not allow that. This is in open litterature on the subject, and it is what I have experienced.

Last point, @Bidja improved the timing of his runs. another point nobody can deny. why for if not for additional air provided by better vanes management ?

I am not a dreamer, nor a liar unlike some people would like others to believe. just sharing what I have seen, measured, and learnt "on the field".

If I were close to your place, I would love to work a few hours on this very subject with you, and any VNT on any car.

 

[Phdv61]

Addendum : closed loop PID was an option I did not select as almost no one would have been able to tune the required tables and coefficients. And I would have needed to work with Nissan motorists. too complex. The simpler, the better.

 

[JakeWild]

This turned up today

It'll be interesting to see how it goes with my mods.

 

[Phdv61]

I am looking forward to your install and tune too !
We keep in touch.

Be careful when connecting the BT ON/OFF red led button ( not needed until your tune is complete. in the mean time, keep the shunt delivered with MB )

gold pin is ground.
opposite pin is +5V from MB
middle goes to the BT pin of MB.

Do not connect any 12V power supply to any of these pins. The button itself will resist, but the BT module would not.

 

[Phdv61]

For anyone who would like to understand a bit more why it is essential to reach mid aperture as fast as possible (but not too slowly, nor too quickly) to take full benefit of the VNT efficiency, and maintain mid aperture as long as possible under load :

read this :

Variable Geometry Turbochargers

And you can conclude by yourself how far from this is your own VNT control.

 

[Phdv61]

By the way, in the Eclipse turbo thread from @Marko_SJ , @geordie4x4 raised a question about controlling an electronic actuator with MB. I will provide some relevant comments here, hoping they won't be censured.

Yes, MB can drive such an actuator as MB already controls the solenoid with pwm signals.
The pwm base frequency used by MB is the one required by the Nissan or Pierburg Solenoid. Electronic Actuators might require a different - lower frequency. 5' job. Easy.

All what you would need is to source an electronic - pwm driven/controlled ( not CAN) - actuator, like the Hella one, and design the necessary mechanical adaptations.

Be careful, as there are two versions on the market. Many are pre-wired to accept both pwm or CAN control, some only one of the two. And some are dual wired, but only have a firmware for one or the other use.

In any case, watch also carefully the temperature around your electronic actuator, as the heat shield is close, and an electronic actuator has... electronic components inside. Modern car turbo 'arrangements' are designed with this high temp environment in mind.
Some car manufacturers did not (or do n ot ) select an electronic actuator for that very reason : temp. It is rather hot under the bonnet !

MB is a hw-sw product which allows you to control such an actuator 'by the book', providing you fill up the right "turbo map" as explained in MB documentation.

That said, even if your pneumatic stock vacuum actuator is not as "responsive" as a stepper motor, it won't make a huge difference on our Patrols. Why for ? The vanes positioning accuracy reached by MB is better than 0.1mm. and the position is updated more than 12 times per second ( more than what is really needed in fact), which is every 80ms. So even if you get a few tens of ms "pneumatic delay", it won't change the face of the world and what you feel when driving nor the performance. We have vacuum, a solenoid, and a vacuum controlled actuator on our Patrol. All good, reliable components. So why bother going to an electronic actuator imo ?. But you can if you wish to do so.

Last but not least, and I fully agree with @geordie4x4 , replacing a stepper motor properly driven by an ECU on a car by a positive pressure actuator is a total non-sense, for the same reason as explained in the previous post : a positive pressure actuator will 'just' continue to open the vanes with boost rising whilst an ECU will open the vanes 'properly' ( unless many mods got the ECM of this gentleman"lost". In that case, MB can help and will allow the best possible outcome to be achieved).

Two 5$ chinese needle will provide the same (in fact better) result as a positive actuator , with more accuracy and a slightly better "performance" as it will be "adaptable" and "tunable" to your own car configuration.

BUT, like valves,it won't be the optimum solution to run a VNT turbo in its 'efficiency zone'.
Laws of physics are ... laws of physics, and apply to everybody whether they like or not.

Read carefully the doc in the previous post, and decide what is best for you, by yourself.

 

[geeyoutoo]

By the way, in the Eclipse turbo thread from @Marko_SJ , @geordie4x4 raised a question about controlling an electronic actuator with MB. I will provide some relevant comments here, hoping they won't be censured.

Phil, you know damned well why I said what I did in the Eclipse thread.
Just to remind you, I had complaints about what was basically advertising in many different threads, also your view that any system other than yours is rubbish, I also said your 2 threads on the MB and 2 or 3 needles are fine. I also mentioned I knew you were working on electronic control, stepper, and that was quite possibly a good thing. Please don't play the victim here, you have had a pretty good run.

 

[Phdv61]

I am not saying it’s « rubbish ».
I have tried initially to share what I discovered, and what is to be done to control a VNT properly. None of the existing arrangements are doing the right thing even if you have the « illusion they do ».
Read the open literature.
It is just a pity for all Patrol users that some continue to deny the evidences very strongly in a sort of « NIH » syndroma.

My plan was to offer you one to congratulate you for all the good work you have done for our community, but I long abandoned the idea.

I decided to make MB available to others to make their Patrol much more enjoyable. Nothing else. This is my main reward.

Last but not least, MB can ALREADY control any pwm electronic actuator. I don’t think it will bring anything more to our Patrols. And I have explained why. I apologize for my English being poor and unclear.

 

[Phdv61]

For anyone who has any difficulty in setting his Magic Box "turbo map", do not hesitate to contact me by PM and/or through the dedicated email I used to send you the PC software and the Smartphone App. Do not forget to send me the VNTxxx.txt file which contains your latest settings, and the relevant listenerxxx.txt file with recorded data.

Reminder : if you drive in altitude and/or in low ambiant pressure conditions, do not touch the limiting screw until your turbo map is fully tuned for everyday's driving, or it will make your tuning more difficult.

 

[Phdv61]

Since some continue to believe they are right to use "manual boost controllers", I thought it woud be more than time to have look at how your stock ECM manages the stock Turbo.

I digged out an old data record made on my 2000 Di with ECUtalk. Altough the OBD2-Consult port only runs at 9600bits/s, and data transfer is quite slow, we are lucky on our Di that the ECM provides its pwm values sent to the Solenoid, so we can track what it does. And we will be able to understand two major points, even if denied by some still advocating the manual boost control against all laws of physics.
1/ the ECM opens the vanes as early as 1250 RPM/1500RPM, and manages the vanes aperture not with the boost value which is not used by the ECM, but the MAF voltage. If the turbo vanes are open properly, it can be demonstrated than the MAF voltage and the MAP voltage are just "homothetic" (I did), and you can use either of the two for boost control.
2/ As soon as you apply mods to your Patrol, the MAF control strategy run by the ECM is lost, and the vanes CAN'T be in the right position all the time anymore. This is due in particular to the fact that the vanes opening is not linear with MAF voltage or MAP voltage increase.

Here are two excel graphs

• one showing, on a manual gearbox, the MAF voltage x 10 ( 35 = 3.5V), the RPM, the pwm value applied by the PATROL ECM to the solenoid, and the TPS voltage (x20 ie 40 = 2.0V TPS ), for gears 2,3,4 vs time in seconds
• the same data, but displayed as PWM % vs MAF voltage. I'll come back on this one further down.

On the second graph above, what can we analyse/see ?

1/ the ECM gets the turbo vanes to open very early, as soon as the MAF voltage exceeds 2.7V ( not much).

2/ At 3.5V MAF, which is what you should get at 2000RPM if your "turbo map" is properly tuned, on a standard inlet ducting, vanes are already mid-open ( 37% pwm). Amazing, no ? I can get up to 3.65V at 2000RPM climbing a hill with my stock inlet ducting and stock turbo, vanes mid-open, and 16psi boost only.

If your vanes are mid-open, you are benefiting from the best efficiency of your Garett turbo.
if your vanes are still closed at 2000RPM, with lots of boost, you have much less very hot air getting into your cylinders due to the back pressure you are fighting with. And then you have to buy a superior intercooler, ... etc etc but you will still have less air getting through. Remember : L E T Y O U R M O T O R B R E A T H E ! ! ! !

3/ When reaching 4V MAF, the ECM increases the opening of the vanes. it is NOT what you wand nor need. But this is what the ECM does.
Please remember also that the MAF voltage does not increase linearly with the g/s of air increase. Between 3.5 and 4V, there is more than twice the amount of air being swallowed by your cylinders.

If you are new to the Magic Box, do not forget to record what you get with your current setting before you set MB up. Then you will be able to compare apples and apples and see any improvement you get.

If you are just visiting this thread but want to improve your current manual boost control arrangement :
1/ go back to your ECM + Solenoid.
2/ Complement it with two 5$ chinese needles, one connected to fresh air, one to the boost line, and both with a T to the actuator hose.

This will allow you
A/ to decrease a bit the initial spool-up ( ex: you blocked your EGR, and/or you now have a 3" exhaust).
B/ to open the vanes a bit more rapidly (second needle) with boost rising to keep your max boost under control.
That second needle is almost fully closed. You open it very very slightly up until you regain control of your max boost.
But this way, you will still keep some benefit of the non-linear opening of the vanes, even if not perfect, and you will also keep the opening of the vanes down low, which is essential for down-low torque.

 

[Phdv61]

To end with this subject of "are you sure that if you get a higher MAF voltage you get more fuel injected ( and conversaly less)", I have put together a graph, for the same time sequence, adding the RPM, the INJ timing control valve value as generated by the ECM, as well as the fuel quantity control valve value as generated by the ECM vs the MAF voltage.
And guess what ? ... The higher the MAF voltage, the higher the fuel quantity. Direct link.
By the way, the injection timing also follows what we already know for the stock fuel map : max Torque is at 2000RPM ( = max mg of fuel per stroke). Can be seen on this graph too.

Here it is :
right scale : RPM
left scale : %PWM control for Solenoid, INJ timing C/V, and fuel Qty C/V.
bottom scale : MAF voltage x 10.

I hope your ECM "behaviour" will be less of a mystery for you from now on.
As explained repeatedly, MAF voltage is the game driver for our Patrol, which is why a good - genuine - MAF sensor is so essential.

On this last point at least, I believe everyone should agree.
But no worries if you want to use another MAF. MB can still manage.

 

[DieselTuner]

Point taken and understood.
But let me disagree.
IF I reduce the MAF voltage by 0.3V (I used to do that in the past to kill limp), I loose a lot of power /Torque.
Since the ECM adds fuel wrt MAF voltage ( quantity of air), the equation less air + less fuel = less power was explainable.
I have therefore difficulties to follow you when you say MAF voltage is not that important, and that I would not see any difference on a dyno.
I am using no remap, the stock fuel table and AFR.
I can drive up in steep mountains in 5th gear whilst in the past I had to go 4. There must be a difference therefore.
And everybody running an MB have shared the same positive experience.

Why would engineers design a clever vanes system for turbo to adjust the flow if a two stage turbo ( vanes fully closed or fully open ) provide the same result. Hard to believe. I can't follow you on that one.

What is sure is that as long as you keep the vanes aroiund 1/2 open ( or 1/2 close) more or less, it is the area where the VNT is the most efficient. Valves do not allow that. This is in open litterature on the subject, and it is what I have experienced.

Last point, @Bidja improved the timing of his runs. another point nobody can deny. why for if not for additional air provided by better vanes management ?

I am not a dreamer, nor a liar unlike some people would like others to believe. just sharing what I have seen, measured, and learnt "on the field".

If I were close to your place, I would love to work a few hours on this very subject with you, and any VNT on any car.

Maf voltage is only important if you have no control over fueling independantly of the maf voltage.

Get some dyno results instead of relying on people timing their stuff on the road or making endless data traces that mean literally nothing to the average person.

 

[Phdv61]

Hi DieselTuner.

Nobody does any "timing on the road". They try to get the maximum airflow from their turbo and keep their boost under control.

I am just trying here to explain once more what our ECM does with showing data sent by the ECM itself. And above all, how the ECM manages the stock turbo vanes. And I am not saying it's right or wrong. Just saying what it does, and why.

Adding more fuel is fine with me. But I hope you will at least agree that if you can get more air in, you can add even more fuel. As a tuner, you should therefore find some interest in this work.

From day one, I have been talking about VNT and "air", and many like you keep answering "fuel". One does not preclude the other. The VNT was invented for good reasons. Why not take the maximum benefit of it instead of under-utilizing it ?

With all due respect to your experience and knowledge in tuning, we are definitely not on the same wavelength.

 

[DieselTuner]

Hi DieselTuner.

Nobody does any "timing on the road". They try to get the maximum airflow from their turbo and keep their boost under control.

I am just trying here to explain once more what our ECM does with showing data sent by the ECM itself. And above all, how the ECM manages the stock turbo vanes. And I am not saying it's right or wrong. Just saying what it does, and why.

Adding more fuel is fine with me. But I hope you will at least agree that if you can get more air in, you can add even more fuel. As a tuner, you should therefore find some interest in this work.

From day one, I have been talking about VNT and "air", and many like you keep answering "fuel". One does not preclude the other. The VNT was invented for good reasons. Why not take the maximum benefit of it instead of under-utilizing it ?

With all due respect to your experience and knowledge in tuning, we are definitely not on the same wavelength.

Maximum airflow from the turbo means less than nothing on a diesel engine mate. Matching airflow to fuel flow is all that matters to be really honest. And we are talking about one of the most rudimentary control systems for a diesel system anywhere in the world. It is barely 20% better than a boost compensated Indirect injected motor.

I love delving into tuning theory and practice, I just dont bother with relatively stock setups any longer because I have proven for a decade or more it is literally a waste of time if you are measuring real world results on a dyno or on the road.
Throw a thousand graphs up with all the data in the world, they mean nothing to me. Give me some hard physical evidence of the gains based on real world results.

Just because you can get more air into the engine, no it doesnt mean you can or should get more fuel into it.

And FYI, fuel is 50% of the equation when it comes to the dynamics of a diesel engine. Even the timing at which the fuel is injected and how it burns makes a massive difference to the output regardless of where the vanes are positioned.

Im more than happy to offer up my time and my dyno and test equipment if you want to try and put your theory into the real world.

 

[Phdv61]

I would not disagree with some of your statements @DieselTuner . But not all.

The ECM firmware ( at least the Di as I tested it) does use MAF voltage/TPS to decide what fuel quantity and which timing it requests the IP to execute. And it makes use of its fueling/Advance timing tables, the ones you are an expert in modifying.

I might be wrong, but if I reduce the MAF voltage electronically accross the board, I do reduce Torque an Power. And vice-versa. Notwithstanding what could be gained in addition by modifying the stock AFR. Not what I was investigating.

I do understand that you are no longer interested in stock fuel maps, but certainly would be in investigating what additional torque/power you can get if you can add more fuel to an increased amount of air.

I really appreciate your offer in working together to see what could be obtained from a joined effort but I am 20 000km away from you. However, may be @trev zd30 or @Bidja could find an interest in embarking on it (Both CRDs).

Trevor has an Eclipse turbo sitting on his shelf, and is currently running a stock Garett turbo, with a remap.
John, has a Pro-charge turbo (and an existing remap too), which gave him headaches to control. Both know their Patrol configuration, and what they had before they installed their respective MBs.

You would need to discuss this directly with both of them, even if, IMO, the Garett and/or Eclipse would probably be a better route to explore. Happy to stay in the loop as the designer and developper of MB.
We could open a different thread on this very subject or a separate 4 ways conversation. Your call. And happy to support any effort. For fun.

 

[geeyoutoo]

@Phdv61 @DieselTuner Further discussion on development is to stay within this thread or as suggested by Phil a multi member PM, the number of members that can be included in a PM has risen considerably under our XF software.

 

[Bidja]

John, has a Pro-charge turbo (and an existing remap too), which gave him headaches to control.

More of a challenge and provided an opportunity to learn so to avoid headaches.

 

[Nikolay]

for me the main question is how to prevent the control unit from turning off the fuel near 4 volts on the mafe for 10 seconds, I have about 3.8 volts, this is the main problem, we install M57 engines from bmw and can put more powerful turbines and efficient nozzles there and nothing prevents you from removing 250 l\s from motors D1

 

[Phdv61]

I am not sure I understand totally your comment. But to suppress limp, you can either go for a remap, suppressing limp like they do in Australia, or let a Magic box take care of it for you.

I have no remap and I can nevertheless exceed all known MAF related limp thresholds under load without any fuel cut.

All what is needed is electronics and software with RPM and MAF input, a timer, and a controlled MAF output not exceeding the known ( RPM, Volts) thresholds for more than 4s.

 

[Phdv61]

reducing the MAF voltage all the time is not a good idea as it reduces fueling accordingly. Ex using an Hitachi or Pierburg MAF generating a lower voltage instead of a Nissan Genuine MAF.