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swinks
22-01-2012, 03:48 PM
Right....
Yesterday I've approached quite interesting discussion o a PL forum.
All this is because one bloke in PL did conversion fl a/t to manual. He used a/t pfl MAF, and after conversion he noticed increased fuel consumption. By simple coincidence he replaced MAF by one from manual fl and fuel consumption gone reasonable as expected.
So... because he knows mapping ecu etc. very well, he did check what's going on in tables etc.

What he noticed is that load maps differ between pfl and fl, also manual and a/t so let's say: 4 different tables of air load. And those tables refer differently to MAF signal, which is also differently defined depending what drivetrain used and fl/pfl version.

At the moment we are in middle of discussion (new thing, yesterday evening came out, I've spent 3hrs on Skype on chat) it's temporary conclusion that it may be an issue that matching MAF to vr4 model is quite significant to fuel consumption and performance, but need to be confirmed that those 4 different MAF types exist.
Anyway I'm still not convinced, having manual image flashed in 7201 (or is it still a/t image with tcl "disabled"...? :undecided NJ to confirm) and pfl a/t MAF my fuel consumption went down, now with V6 TB gone up (as expected). So I'm not a person who may have answers.
And most important, so far I haven't noticed that our MAF's have different serial numbers vary on drivetrain or pfl/fl.

So, all those more familiar with ecu tables and maf scaling may join discussion, please...

lateshow
22-01-2012, 05:21 PM
I have a FL auto with and i've flashed KS mods which is from a manual FL ? I cant say i have noticed any difference ?

But if lambda does it's correction simple MAF misreadings are no problem?

swinks
22-01-2012, 06:18 PM
I have a FL auto with and i've flashed KS mods which is from a manual FL ? I cant say i have noticed any difference ?

But if lambda does it's correction simple MAF misreadings are no problem?
Lauri, by flashing Ken's custom maps you have already altered load maps, this is more about stock maps.

And it's not about MAF readings. Our MAFs have quite wide reading scale. Potential issue is due to different references to MAF reading in ecu load maps depend on what sort of maf is used and ecu. Sort of matching right ecu with right maf.
As said before I'm not an expert, I'm rather referring discussion between few PL blokes who use to do custom maps and flash ecu on daily basis (not specifically for vr4), and this issue came out when they did auto>manual conversion and later did some ecu reading and flashing.
And... it's for now more like hypothesis, because there's just few vr4 in PL do compare ecu's and mafs, hence my thread here.

Davezj
22-01-2012, 10:23 PM
mine VR4 is a pfl auto with traction contol and my MAF Number is MD334005

i also have the chassis numbers of various manual/auto fl/pfl and i all acses the MAF has the same part number MD334005

so i think it is just the maps that will differ.

swinks
22-01-2012, 10:37 PM
so i think it is just the maps that will differ.
That's what I was thinking, but better check twice.

Davezj
22-01-2012, 11:16 PM
just out of interest what tables/code does the drivetrain/model recognition?
and where are the other fuel tables?
i presume it is something that we do not have in our definition file yet, as i don't see more than 2 hi and 2 low octane fuel map tables.
and both the two hi and two low fuel maps are the same.

swinks
23-01-2012, 01:02 AM
We were talking about load maps (or how it would be in English..., air load?), not fuel.
At he disassembled ecu image and extracted such kind of maps as well.

Davezj
23-01-2012, 01:20 AM
do you know what the tables are called or what the Hex address of the tables are just to see if we have these tables defined as a different name.

i am only asking out of general interest Tomasz, i have not got my head round the ECU modding thing.
but i have all the stufff to modify and flash the ecu's.
i want to get my head round how it all fits together before i go changing stuff, but at the moment i am just not getting it, i am not seeing the relationships between the tables how they are linked and effect eachother.

kinkyafro
23-01-2012, 11:38 PM
A manual ecu vs an auto ecu might make a slight difference but I wouldn't expect the maf to make any difference (unless it was broken). The 4 tables are two low octane maps one high octane manual map and one high octane Auto map.

Also the maps don't differ between between fl/pfl

Finally Tomasz your 7201 will be a manual image.

Davezj
24-01-2012, 12:20 AM
Well in that case, I have looked at the two hi octane maps and they are the same so there is no difference between the manual or auto factory fuel maps.
You should be able to see a difference in either the WGDC (2 maps) or the 4 Boost Desired Engine Load-A, B, C Or D or the 4 Loadboost scale BDEL-A, B, C or D.

Differences in these table I would assume would account or the 260bhp auto and the 280bhp manual in PFL spec.
So I would also presume a FL ecu rom would have the same values in the above tables.
But I don't have a FL rom to compare it to.

But this is only theory.

adaxo
24-01-2012, 03:40 AM
/Hijack

i want to get my head round how it all fits together before i go changing stuff, but at the moment i am just not getting it, i am not seeing the relationships between the tables how they are linked and effect eachother.

But I don't have a FL rom to compare it to.

You know where to look, don't you??/Hmmm
You welcome to start experiments on my ECU, may we can learn something from each other till someone better on this subject write a proper guide how to tune ours ECUs:lost:
:coat

Davezj
26-01-2012, 11:53 PM
I am sure keneths ecu roms will come with boost control on it.
And I seem to remember another thread about controlling boost through the factory ecu.
But I never really understood what was being said.

lateshow
27-01-2012, 10:04 AM
Now are we talking about Airf Flow (Hz) vs Engine load map, cause that can be seen at least in some definitions?

foxdie
27-01-2012, 10:23 AM
I am sure keneths ecu roms will come with boost control on it.
And I seem to remember another thread about controlling boost through the factory ecu.
But I never really understood what was being said.

In addition to the stock ROMs that Mitsubishi supplied, both Kens 1.x and 2.0 Beta ROMs offer boost control via load target (Boost Desired Engine Load), although maintaining a perfectly stable boost through the rev range is a tricky and delicate process.

On my car for example, I've noticed when I floor it around 3000-4000ish RPM, my car will spike to 1.3-1.4 bar before settling down to 1.1-1.2, however accelerating from a lower speed the boost is much more stable. If I back off the WGDC (Wastegate Duty Cycle) so it's not as aggressive at building boost, I notice I can't make the same amount of boost.

Boost control via ECU is all about how fast the ECU can detect (via load calculations) and then compensate (via adjusting the wastegate) for changes in manifold pressure. Some older (or cheaper) electronic boost controllers have this same issue, they can't react as fast as is sometimes required and you end up either overboosting or underboosting. Boost control via ECU isn't perfect, but it's good for those on a budget and can't afford to spend another £300+ on a decent EBC when you still need to reflash the ECU to remove the boost cut and implement supporting mods.

Kens plan is to implement MAP sensor support to accurately control boost and hopefully with BCXs advise implement live mapping, at this point our ECUs will approach a level of sophistication to start to be a threat to the big boy ECUs such as Megasquirt and possibly even ViPECs.

Anyway, I digress, this is starting to become off-topic :)

Shtiv
27-01-2012, 10:26 AM
MAF's are all the same as far as i have seen, auto/facelift/pre facelift, also I think all autos are 260hp and all manuals are 280hp regardless of fl or pfl.

lateshow
27-01-2012, 10:51 AM
MAF's are all the same as far as i have seen, auto/facelift/pre facelift, also I think all autos are 260hp and all manuals are 280hp regardless of fl or pfl.

Could be, since dyno results mostly give around 260bhp to stock auto's. Maybe it is just the gearbox...

foxdie
27-01-2012, 10:54 AM
I thought facelift autos made 280 as well?

lateshow
27-01-2012, 11:11 AM
I thought facelift autos made 280 as well?
We were just thinking that yes they are said to be has anyone dynoed a stock FL with suhc a good results.

horndog
28-01-2012, 12:38 AM
oops sorry ignore me

wintertidenz
28-01-2012, 02:38 AM
CANDEE's FL auto made 181kW at the wheels, so around 240HP.

His was stock too from memory.

CANDEE
28-01-2012, 05:48 AM
It ran 167kwatw with nothing done at all(was apparently running 15w50 or something weird oil too)..

It did the 181 run with just a ralliart panel filter, maf mod and amsoil 0w30.

The last run was 174kw with only an exhaust change and Motul 10w40, but it was down 1psi of boost which could have been attributed to the battery reset on stale fuel.

All runs have been done on the same dyno with the same operator. :)

Shtiv
01-02-2012, 11:28 AM
The reason I say all the autos are the same is all auto roms I have seen run less boost, irrespective of fl or pfl, they use a different boost control table to the manual and that table is the same across all autos. the only other option is that the restricor pill is very slightly different between fl and pfl but I've looked at a heap and they're all the same so far. besides why would a manufacturer change a metal piece of hardware that they spent effort developing when they could just change the ecu data. Until I see something telling me why they're different I say all autos are 260 and all manuals are 280 spec.