MAF handling and settings: MS3 vs Bosch Motronic

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MAF handling and settings: MS3 vs Bosch Motronic

Postby nuvolarossa » Sat Mar 12, 2011 5:20 am

I want to try MAF with my MS3.
I'm coming from a week reading deeply about Bosch Motronic... so I know how that handles Load and its definition is this:

Motronic needs exactly three things to calculate LOAD.

1) A signal from the air meter, normalized to "Q" airflow in kg/hr

2) A measure of current engine rpm "n"

3) A programmed injector size constant "Ki" (K sub eye)

LOAD aka Tl (Tee sub ell) is calculated as:

Tl = Q / (n * Ki)

LOAD is not just a representation of cylinder filling, but the
theoretical Injector Time Open (Ti, Tee sub eye) needed to reach
stoich (Lambda= 1) with the current injector setup assuming that
the motor is "perfect".

Which it isn't, hence there are fueling tables which are used as
multiplicative corrections to LOAD to reach the actual Ti.

Hope this clarifies.

Jim Conforti.

Well, here's the math if you have a MAF that produces an analog voltage as
a function of the airmass

First find Q ...

Q=f(Up/Uv) where Up/Uv is the ratio of the MAF output to reference voltages

(Bosch meters are logarithmic/exponential)

From Q, the speed of the engine (n, in rpms) and a CONSTANT (Ki)
which quantifies the fuel injector flow rate we can calculate
the LOAD SIGNAL (Tl) which is effectively the THEORETICAL (Lambda=1)
injector open time for the currently inducted amount of air
per engine cycle or stroke (depending on whether we have a
batch, semi-sequential, or sequential EFI system).

Tl = Q / (n * Ki)

With Tl quantified, we now take into account the vagarities
of the particular engine family and operating conditions by
introducing multiplicative factors to correct the theoretical
injector time to the ACTUAL time for injection (Ti) needed
at that instant. Finally an ADDITIVE factor (Tv) is added to
compensate for the differing injector opening time under lower
than nominal voltages.


Ti = (Tl * [C,D,E...]) + Tv


It is this signal (Ti) that is applied to the injectors

Hope this helps, it's from a BOSCH primer I'm writing ...

Jim




So now I have some confusion about how MS3 handle MAF and what Load really is in MS3 maps.

--- I need to know what I have to do to use MAF in ms3. and maybe to resume all info in one topic, since it's all scattered and there aren't deep docs in MS3 manual

1) I know I need a MAF transfer function. I have it, it's 0-5v in kg/h. I'll convert it to adc counts and upload it with tunerstudio. Plenty of docs about this

2) I set in TS:
control algorythm -- MAF
secondary fuel load - disabled
multiply MAP -- don't multiply
incorporate AFRtarget don't include AFRtarget ????? this is ok?
primary ignition load -- MAFMAP
secondary ignition load -- disabled.
AFR table load -- use primary load (algorithm)
EAE table load -- use primary load (algorithm)

3) what I should do with VE table? (engine ran until now in SD, so they are all tuned by MAP)... bosch motronic uses fuel maps as "
multiplicative corrections to LOAD to reach the actual Ti(injector time open)". MS3 manual says that when using MAF as control algorythm VE tables are not used. So I could leave them as they are(SD tuned values)?

4) If I tune with 19# injectors in MS3, then I swap 42lbs injectors, following motronic logic I should change Reqfuel and inj dead-time, small pulsewidths and I should be ready to drive in minutes and near perfect tune... It's right with MS3 too?

5) Maf correction table... what's its use if I already have a perfect maf transfer function? nothing, right?

6) I'm speaking MS3 vs motronic because I have all maps from motronic that I may be able to use with some conversion, fuel, ignition, WUE, ASE, something like EAE etc. and it would be nice to be able to use in some way some of them.

as you can see I have some confusion about tuning with MAF and MS3...
:RTFM:
Roberto
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nuvolarossa
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Re: MAF handling and settings: MS3 vs Bosch Motronic

Postby VolvoGuy50 » Sat Mar 12, 2011 9:02 am

nuvolarossa wrote:I want to try MAF with my MS3.
I'm coming from a week reading deeply about Bosch Motronic... so I know how that handles Load and its definition is this:

Motronic needs exactly three things to calculate LOAD.

1) A signal from the air meter, normalized to "Q" airflow in kg/hr

2) A measure of current engine rpm "n"

3) A programmed injector size constant "Ki" (K sub eye)

LOAD aka Tl (Tee sub ell) is calculated as:

Tl = Q / (n * Ki)

LOAD is not just a representation of cylinder filling, but the
theoretical Injector Time Open (Ti, Tee sub eye) needed to reach
stoich (Lambda= 1) with the current injector setup assuming that
the motor is "perfect".

Which it isn't, hence there are fueling tables which are used as
multiplicative corrections to LOAD to reach the actual Ti.

Hope this clarifies.

Jim Conforti.

Well, here's the math if you have a MAF that produces an analog voltage as
a function of the airmass

First find Q ...

Q=f(Up/Uv) where Up/Uv is the ratio of the MAF output to reference voltages

(Bosch meters are logarithmic/exponential)

From Q, the speed of the engine (n, in rpms) and a CONSTANT (Ki)
which quantifies the fuel injector flow rate we can calculate
the LOAD SIGNAL (Tl) which is effectively the THEORETICAL (Lambda=1)
injector open time for the currently inducted amount of air
per engine cycle or stroke (depending on whether we have a
batch, semi-sequential, or sequential EFI system).

Tl = Q / (n * Ki)

With Tl quantified, we now take into account the vagarities
of the particular engine family and operating conditions by
introducing multiplicative factors to correct the theoretical
injector time to the ACTUAL time for injection (Ti) needed
at that instant. Finally an ADDITIVE factor (Tv) is added to
compensate for the differing injector opening time under lower
than nominal voltages.


Ti = (Tl * [C,D,E...]) + Tv


It is this signal (Ti) that is applied to the injectors

Hope this helps, it's from a BOSCH primer I'm writing ...

Jim




So now I have some confusion about how MS3 handle MAF and what Load really is in MS3 maps.

--- I need to know what I have to do to use MAF in ms3. and maybe to resume all info in one topic, since it's all scattered and there aren't deep docs in MS3 manual

1) I know I need a MAF transfer function. I have it, it's 0-5v in kg/h. I'll convert it to adc counts and upload it with tunerstudio. Plenty of docs about this

2) I set in TS:
control algorythm -- MAF
secondary fuel load - disabled
multiply MAP -- don't multiply
incorporate AFRtarget don't include AFRtarget ????? this is ok?
primary ignition load -- MAFMAP
secondary ignition load -- disabled.
AFR table load -- use primary load (algorithm)
EAE table load -- use primary load (algorithm)

3) what I should do with VE table? (engine ran until now in SD, so they are all tuned by MAP)... bosch motronic uses fuel maps as "
multiplicative corrections to LOAD to reach the actual Ti(injector time open)". MS3 manual says that when using MAF as control algorythm VE tables are not used. So I could leave them as they are(SD tuned values)?

4) If I tune with 19# injectors in MS3, then I swap 42lbs injectors, following motronic logic I should change Reqfuel and inj dead-time, small pulsewidths and I should be ready to drive in minutes and near perfect tune... It's right with MS3 too?

5) Maf correction table... what's its use if I already have a perfect maf transfer function? nothing, right?

6) I'm speaking MS3 vs motronic because I have all maps from motronic that I may be able to use with some conversion, fuel, ignition, WUE, ASE, something like EAE etc. and it would be nice to be able to use in some way some of them.

as you can see I have some confusion about tuning with MAF and MS3...
:RTFM:

What kind of car is it that you're doing this with?

2 - I think you're good there, but I'd change includeAFR to yes. That's the way most Motronic ECU's do it since they only have a narrowband O2.

3 - You are correct in saying the VE fuel maps aren't used, at least according to the docs. I think they're supposed to disappear, but I don't know for sure.

4 - Yep. That's what MAF mode is all about!

5 - in your case, "nothing" is correct. If you've already put your info into the INI file manually, then this window is useless.

6 - yes, it is possible; but not easy at the least. I was pondering running MAF mode and translating the Motronic 4.4 custom-tuned maps I have, but I didn't feel it was worth my time, given that MAF's are about $150 for my car and they're one of the few parts in my car which has a horrid track for reliability.
1992 Volvo 740 Wagon - Beater Car...CAI, 16T, catback, MS3/MS3X, & HID's
1996 Eagle Talon TSi AWD - Daily Driver...RAI, Big 16g, 3" TBE, HID's, etc.
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Re: MAF handling and settings: MS3 vs Bosch Motronic

Postby nuvolarossa » Sat Mar 12, 2011 9:50 am

Car is a BMW 318is, M44 engine (1.9L, 4cyl), oem uses Bosch Motronic M5.2 with MAF.
Car was then turbocharged at low boost with stock ecu and piggyback, for a while before the ms3, but now is stock naturally aspirated.
I'll surely reboost it later, but as now I want to explore and learn all MS3 functions, learn deeply how to control the engine knowing 100% what I'm doing.
I removed the turbo to have less variables/complications, so car now is stock.

Using MAF is one of my "learning" objectives, as well MAF+MAP when I'll reinstall the turbo.
I want to try MAF because that's how the car was born and for a few other little "troubles" (poor desire to fine tune soon some rare conditions). I'd simply like to see how ms3 behaves with MAF. :P
----
I know that using Motronic data the way is stored is hard... but you know, inside motronic there are knock sensors reference tables and other things that could be useful in future.
All OEM tables are the result of a lot of R&D already done, there are already well mapped timing map, AFR and inj angles already spot on for that engine...

I know, I'm pretty happy the way my MS3 goes now in SD mode, but timing map is not dyno mapped and I would be curious how motronic timing map (RPM vs uS load) would be against what I'm using now with MAP and this goes on for all other settings.
I've not tried a lot of AFRs at idle, injection angles etc... all of that is already inside the motronic, if you can read or if you have the right tools to read/understand/decrypt it.

At the end of the day it might be too much work for only a few improvements, barely noticeable...
reinventing the wheel, but I would enjoy to try it.
I bought MS3 to learn. :D :RTFM:

EDIT:
VolvoGuy50 wrote:3 - You are correct in saying the VE fuel maps aren't used, at least according to the docs. I think they're supposed to disappear, but I don't know for sure.

they don't disappear!!! so what I should set them to?
Roberto
MS3x 1.3.0 | TS beta 2.6.01
nuvolarossa
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Posts: 276
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Re: MAF handling and settings: MS3 vs Bosch Motronic

Postby ashford » Sat Mar 12, 2011 11:38 am

nuvolarossa wrote:Car is a BMW 318is, M44 engine (1.9L, 4cyl), oem uses Bosch Motronic M5.2 with MAF.
Car was then turbocharged at low boost with stock ecu and piggyback, for a while before the ms3, but now is stock naturally aspirated.
I'll surely reboost it later, but as now I want to explore and learn all MS3 functions, learn deeply how to control the engine knowing 100% what I'm doing.
I removed the turbo to have less variables/complications, so car now is stock.

Using MAF is one of my "learning" objectives, as well MAF+MAP when I'll reinstall the turbo.
I want to try MAF because that's how the car was born and for a few other little "troubles" (poor desire to fine tune soon some rare conditions). I'd simply like to see how ms3 behaves with MAF. :P
----
I know that using Motronic data the way is stored is hard... but you know, inside motronic there are knock sensors reference tables and other things that could be useful in future.
All OEM tables are the result of a lot of R&D already done, there are already well mapped timing map, AFR and inj angles already spot on for that engine...

I know, I'm pretty happy the way my MS3 goes now in SD mode, but timing map is not dyno mapped and I would be curious how motronic timing map (RPM vs uS load) would be against what I'm using now with MAP and this goes on for all other settings.
I've not tried a lot of AFRs at idle, injection angles etc... all of that is already inside the motronic, if you can read or if you have the right tools to read/understand/decrypt it.

At the end of the day it might be too much work for only a few improvements, barely noticeable...
reinventing the wheel, but I would enjoy to try it.
I bought MS3 to learn. :D :RTFM:

EDIT:
VolvoGuy50 wrote:3 - You are correct in saying the VE fuel maps aren't used, at least according to the docs. I think they're supposed to disappear, but I don't know for sure.

they don't disappear!!! so what I should set them to?


ve1 does absolutly nothing.
you can turn on secondary fuel load(ve2) and set it to multiply, enter all 100's in the bins and now this is your trim table
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Re: MAF handling and settings: MS3 vs Bosch Motronic

Postby VolvoGuy50 » Sat Mar 12, 2011 3:48 pm

ashford wrote:ve1 does absolutly nothing.
you can turn on secondary fuel load(ve2) and set it to multiply, enter all 100's in the bins and now this is your trim table

Thanks. That's what I assumed. Not sure why it just won't go away, but whatever. :lol:

nuvolarossa wrote:Car is a BMW 318is, M44 engine (1.9L, 4cyl), oem uses Bosch Motronic M5.2 with MAF.

I've not tried a lot of AFRs at idle, injection angles etc... all of that is already inside the motronic, if you can read or if you have the right tools to read/understand/decrypt it.

At the end of the day it might be too much work for only a few improvements, barely noticeable...
reinventing the wheel, but I would enjoy to try it.

You can find the BIN file online if you don't have the tools to dump the EEPROM yourself. The software is free and is called Motronic Suite. There are others, but they cost a quite large sum of money to get. (i.e. WinOLS). A word of warning - Bosch gets lazy with their mapping and their tables are confusing to look though. Just be sure to check what table you're looking and it's not that bad.

nuvolarossa wrote:I bought MS3 to learn. :D :RTFM:

That's what MS in-general is for. And any standalone, MS or anything else won't gain you much on a stock engine like yours or my current one. Even fully tuned to the best possible way, an EMS will only give some gains as you will be held back by the mechanical stuff. Again though - it's all a learning experience.
1992 Volvo 740 Wagon - Beater Car...CAI, 16T, catback, MS3/MS3X, & HID's
1996 Eagle Talon TSi AWD - Daily Driver...RAI, Big 16g, 3" TBE, HID's, etc.
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Joined: Sat Jan 01, 2011 4:42 pm
Location: Burlington, CT USA

Re: MAF handling and settings: MS3 vs Bosch Motronic

Postby nuvolarossa » Sat Mar 12, 2011 5:09 pm

VolvoGuy50 wrote:You can find the BIN file online if you don't have the tools to dump the EEPROM yourself. The software is free and is called Motronic Suite. There are others, but they cost a quite large sum of money to get. (i.e. WinOLS). A word of warning - Bosch gets lazy with their mapping and their tables are confusing to look though. Just be sure to check what table you're looking and it's not that bad.

motronic suite :lol: ok I see you're in volvo world. I was being vague! even if you dump your bin and learn the map pointers and how maps works, you wouln't know factors and offset to have data in real units. even if you disassemble the code you don't get factors. you can go "by eye" if you tune easy maps like fuel and advance, but when you need detailed axis like temp, time or some other particular maps you need something more you don't have in your dump....you know about .a2l or .dam extensions? :mrgreen:

VolvoGuy50 wrote:
nuvolarossa wrote:I bought MS3 to learn. :D :RTFM:

That's what MS in-general is for. And any standalone, MS or anything else won't gain you much on a stock engine like yours or my current one. Even fully tuned to the best possible way, an EMS will only give some gains as you will be held back by the mechanical stuff. Again though - it's all a learning experience.

I know that, as I said I don't want power from this car. I'm not switching to MAF for power... I want the learning experience. I have other cars with more cylinders for more power. This car is "my MS lab" because it has a simple engine :D

Thank you all for the info in this forum. I've found the ini mod for vetable2 and TS veal. I hope to try MAF and double check transfer function really soon (via diagnostic software), so I can document more.
Roberto
MS3x 1.3.0 | TS beta 2.6.01
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Posts: 276
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Re: MAF handling and settings: MS3 vs Bosch Motronic

Postby VolvoGuy50 » Sun Mar 13, 2011 12:25 am

nuvolarossa wrote:
VolvoGuy50 wrote:You can find the BIN file online if you don't have the tools to dump the EEPROM yourself. The software is free and is called Motronic Suite. There are others, but they cost a quite large sum of money to get. (i.e. WinOLS). A word of warning - Bosch gets lazy with their mapping and their tables are confusing to look though. Just be sure to check what table you're looking and it's not that bad.

motronic suite :lol: ok I see you're in volvo world. I was being vague! even if you dump your bin and learn the map pointers and how maps works, you wouln't know factors and offset to have data in real units. even if you disassemble the code you don't get factors. you can go "by eye" if you tune easy maps like fuel and advance, but when you need detailed axis like temp, time or some other particular maps you need something more you don't have in your dump....you know about .a2l or .dam extensions? :mrgreen:

:lol: Yeah, I'm in the Volvo world quite a lot. WinOLS has a good Motronic plugin, but I haven't messed with it in quite a while since I'm pretty much at the limit of what the ECU can do on a hardware level. Hence I have up and switched to MS3.
1992 Volvo 740 Wagon - Beater Car...CAI, 16T, catback, MS3/MS3X, & HID's
1996 Eagle Talon TSi AWD - Daily Driver...RAI, Big 16g, 3" TBE, HID's, etc.
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