Make your own MAF conversion for under $50, I did it

**IPM** · 01-05-2010, 12:56 PM

Originally Posted by hakentt

You got motronic 1.0 with ecu number 0 261 200 027
That is even easier to tune for MAF, but I don't have a 84-87 car to test it on,

Why easier? Is there really only the single 1x32 to be concerned with? No 1x8?

**DmcL** · 07-03-2010, 04:13 PM

bump for an oldie but a goodie...

im just getting setup with ostrich, a reader/burner and i nthe next couple of days a wideband. i build the same volvo MAF conversion as hakentt but im having issues with severe flatspots above 4000rpm. it was worse originally but i managed to get it running "normally" below 4000rpm at both WOT and part throttle. cant seem to do anything to affect the breakup in power after 4000rpm tho.. dont want to increase/decrease map values too much till ive got my wideband and can see exactly whats going on with my AFR's. im running 19lb injectors from an M30 and have tried a map for 19lb's and the volvo MAF but it ran worse than the normal volvo MAF map, which also ran worse than a volvo MAF map with some ignition advance oddly.. all hakentt's maps FWIW. think it must be something to do with my car being a euro model or something? main differences that im aware of between mine and USA models is i have no charcoal canister and no lambda sensor. my engine is one of the later lower compression M20's also.. despite worse running on the 19lb map i still suspect its going horribly rich up top but without wideband im not brave enough to keep leaning out high end values till the flatspots go away lol

im hoping that once ive figured that out and have the car running good all the way up to the redline i can take an alpina B3 map i copied from a chip i have here and adjust that to work with the MAF because it seems to give much better low/mid range power than any of the other maps i have tried (on stock AFM). the trouble there is that after i copied the alpina map off the chip and compared it to a stock map (or any other map ive got atm including dinan), the alpina map is totally different in nearly every area and every individual map. it looks like alpina designed their map from scratch whereas it seems like any aftermarket or home made maps i have seen to date are based on a stock map and then modified.

hakentt dont know where u been hiding lately but get ur beehind on the computer and help me figure this stuff out lol... ofcourse since its mutual back scratching im after here ill gladly send u the B3 map, also have a lightly tweaked B3 map tho only 1 value has been changed compared to the original B3 map so far as i can tell..

**hakentt** · 07-03-2010, 04:40 PM

Alpina map is just stock program with advanced timing maps. Alpina software will not work at all with MAF upgrade. And if your car does not have Lambda sensor then my maps won't work. All USA Motronic 1.3 use lambda sensor heavily. Sense you got ostrich2 and my maps and tunerpro is only good for the USA models, you will have to create your own XDF file and create your own tunes using original bin file from your ecu.

**DmcL** · 07-03-2010, 06:13 PM

it runs pretty good with the stock AFM and your 91+ octane map. runs fine on a stock USA 173 map also.

if the mapping is done with the lambda sensor unplugged on your USA models then it should stille be running whatever AFR was set on the map.. i just dont have the ECU's ability to adjust the mixture via lambda sensor.

im not into computers/binary/hex enough to make my own .xdf and i doubt i ever will be tbh.

tell me this.. does your bigger maps xdf work ok for comparing a bigger maps bin ur working on with a normal (ie not expanded maps) bin for the purpose of comparing and copying values from the normal bin to the bigger maps bin? some values seem to cross over so to speak but im not sure if most of it would be right or if id basically not be seeing some of the individual smaller maps on the normal map with the bigger maps xdf?

also im not sure what alpina map u are thinking about but i can assure u there is much more to the map that i have than just advanced timing maps.. u would nearly think u are looking at a map for another make/model of car ffs.

example:

(larger screenshot here http://img36.imageshack.us/img36/751...vsstock173.jpg)

and nearly every small map within the overall map is as different from stock as these are..

like i said.. if u want a copy of the bin to check out yourself hit me up.

**mrhello123** · 02-23-2011, 03:45 AM

I have BMW 87 e32 and I have some problem with it. once I start the engine, it is shaking and blowing from the exhaust and whenever I press the accelerator it became slower and seems that going to be stop I mean to say that I can't give it a fequent race. I have done several things like changed the sensors throttle, sensor fuel pump, spark plug distributor, idle value and whatever related to the sensors have changed all that but still no use even I have changed the engine itself but everything same as before. I have no idea about the ECU and AFM, which one is having problem or there is problem in the wiring system. Because once I remove the cable form ECU and battery and but it back after 5 mints then everything became normal for around 5 to 6 hrs then became everything same as before. My car is having ECU 0261 200 150 and I have changed it before for the same problem. Even I have checked with 0261 200 178 and 0261 200 179 but by both ECU makes more problem and engine start making missing problem. Please help me to solve this issue.

Regards

**ironH** · 03-07-2011, 08:34 AM

Hi
Are there any results for the m42?
I´ve done the COP and for now searching a conversion for the LMM to MAF ;-)

**crazyfaizy** · 09-14-2011, 02:32 AM

hello im lookinmg for a MAF conversion for my 1984 bmw e23 745i turbo
i was woudering if you can help me with this ?
they have discountinued the miller performnace for the turbo version
IF only i can go back in time to get one.....

**DmcL** · 09-14-2011, 01:54 PM

wow old thread lol

@ mrhello123, sounds like there is a sensor that is causing the problem somewhere, maybe lambda sensor sending faulty readings to the ECU or bad coolant temp sensor?

@ ironh, none that im aware of, someone with an M42 will have to pioneer a MAF tune. will be more or less the same as what has to be done to the tune on an M20 to run a MAF.

@ crazyfaizy, same as above, someone needs to pioneer a tune for a MAF for that engine/ECU.

for anyone else who sees this thread and thinks "oh great ill do a MAF conversion on my M20" there are some points to note. first of all the volvo MAF is too small, you will want the 80mm (OD) 0 281 002 120 MAF which is larger than the volvo MAF but the sensor in the MAF appears to have the same output as the volvo sensor as i have swapped a volvo sensor into the larger housing and it ran the same as the original 80mm MAF sensor. the volvo MAF may work for a 320i tho.. second thing to note, none of the tunes shared by hakentt/revlimit for the volvo MAF conversion work 100%, they all have issues. when i first did my volvo MAF conversion i took one of the files that ran the best and tuned it to get it working ok but even then it was sketchy at best and running very rich. fast forward to recently and i discovered the 80mm MAF (part number mentioned above) will work and i made a tune for that from scratch which is running better than any other MAF/tune setup i tried previously, its still got a few glitches but its running good enough for me to daily drive the car on a MAF. ive been driving on the 80mm MAF for probably around 2 months now with no problems other than some areas of the tune which still need a little more work (im a perfectionist lol).

**dangerwillrbnsn** · 10-24-2011, 12:31 PM

Good read here guys, nice pioneering... thank you.

I'm wondering how this would work on an '87 535is, running Motronic Basic. I assume I'd need to do some homework to find a larger diameter MAF to help compensate for the higher volume of airflow into the M30B35?

**DmcL** · 10-24-2011, 03:58 PM

not worth the hassle unless u have alot of free time and know most of the raw code contained in older motronic files.

the volvo MAF for the M20B25 is actually too small which was part of my problem. i have since tuned a file from scratch using the same volvo MAF sensor but in a larger 3 inch housing which worked well and didnt have any random cutting out at WOT or just below.

not all that much difference between a well tuned MAF + stock ECU setup and a well tuned stock ECU + stock (or for the M20, M30 AFM swap).

also theres like no one that knows how to do this kind of stuff from scratch as far as i can find besides myself, hakentt and miller.

if u want MAF, MAP or anything else instead of a similar era flap AFM ur best off going with aftermarket management, its 10x harder to work with standard ECU's.

**razor876** · 04-11-2012, 04:43 PM

Hey there MAF gurus! I apologize up front if you guys feel this subject has been beaten into the ground but I have a few questions for you.

My AFM is a piece of garbage. I took it apart and theres a big groove cut into the material that the meter runs on.

So I get cutting out and power loss intermittently during acceleration. Also the car is running rich. I suspect my AFM for these reasons.

Which is why I was excited when I stumbled across the AFM to MAF conversion that you guys are/were spearheading. Yeah I can pay 400.00 for a MILLER MAF

conversion. But I'd rather save 350.00 doing it your way. Anyway, long story short, did you guys ever perfect your conversion? I have an 87 325ic with a 173

ecu. Could I actually do this conversion? Or have you basically squashed this whole thing?

**RossA** · 06-07-2012, 12:00 PM

Interested in doing this. I have a 6 pin MAF off of a 325i (not sure if this one will work with my 173 ecu). Also, where might I find the mapping for the ecu chip that OP has available? any help would be appreciated. Thanks!