Stock ECU MAF replacement project

[prj]

@prj

thank you for criticizing my offer ;-) without ever holding the PKM solution in your own hands ;-) so tell us why you aware of that even though you are planning to develop the same?? I am confused about that. The PKM box is used in many S2 for years now... up to 750HP...

It works and PKM knowns much what he is doing...

http://www.myvideo.de/watch/8104274/S2_backfire

Because for a custom tune, that box is not needed.
Everything can be done by recalibrating the Motronic properly, instead of using a piggyback.

Unfortunately, not even DAMOS or Funktionsrahmen will help you calibrate the Motronic for a different MAF.
A full disassemble and tracing electronics with a scope at many points is needed to understand how it works.

Funktionsrahmen just says "KFUN"... without much explanation.
I believe Bosch calibrated the LMM using a special in house tool, which no one has.

P.S.
I have got 3 cars running in russia with HFM5 connected directly to ECU, 1 car in UK and 2 cars in Estonia.
No box needed!

[blackS2]

@mrtat2k9

My stuff on bay... so ask me everything you want...



@prj

thank you for criticizing my offer ;-) without ever holding the PKM solution in your own hands ;-) so tell us why you aware of that even though you are planning to develop the same?? I am confused about that. The PKM box is used in many S2 for years now... up to 750HP...

It works and PKM knows much what he is doing...

http://www.myvideo.de/watch/8104274/S2_backfire

[prj]

Not really useful no.
I am aware of what that is, and yes I need to develop the same box, but it's pretty easy to do. Just don't have time.

[mrtat2k9]

dont know if this is any help. its in german but maybe some one could translate it for us
german ebay 250932405608

[diesel des]

I have broke 3 maf wires with gt2871. Now happy on vems...

[prj]

I got some great help and ideas from Shane regarding measurements and simulating airflow.
Now I just need to finish designing the board and knock up a prototype.
Because things are still quite busy ATM, I think it is more likely to happen during winter.

[A80Avant]

I don't know how many stock cars you have seen with wires gone, but all the rs2 I know about 8 from Greece and most discussions on this forum from 2004 that I first started reading, and I can say that almost all of them that had problems, was with the wire in. Sometimes wiring issues as well.

I would say that the hfm will be better of it can be more robust on those areas, and of course without doubt will be dead cheaper to replace whenever it goes bad.

Keep it up!

sent using Android

[prj]

Broken wires are not a myth, seen so many with my own eyes, but that is not why I am doing this.
For big power cars I have the RS4 MAF solution that has been now extensively tested and happily works to 600-700 hp.

This would be indeed so that people don't start writing off cars because new MAF costs gazillion euros... or is NLA.
It will be possible to fit on any stock or not stock car, that before used the original MAF.

Of course, it will not be able to read more, or provide better range than the original, as the idea is to exactly duplicate the original's output, but it will give the ability to have a much more durable MAF and even if anything happens to it, after a one time fee of about 200 euros, it will be possible to replace the MAF sensor for 65 euros as many times as you like. I am not going to scrape the codes off the sensors or anything stupid like that.

So the idea really is to just make something that is better than the current offering for less money than the current offering, and the deeper meaning is of course to keep as many of these old cars on the road as possible.

[A80Avant]

excactly
i agree with you, but for that matter, the bigger RS4 maf, solves the problem!

[Thuppu]

Ooh, so it was only a replacement for stock cars? To bad for them who have uprated engines...

My point was that the MAF threads can hold on a 400+hp engine if you don't use the full power much. But on the other side, it can break the first time you hit the pedal if you are unlucky. You newer know. But when your power usage is almost 100% at long periods, like on track, the chance is much greater that the threads break.

[A80Avant]

Please take the time to at least read fully what i write before quoting only what suits your post...

i have said it twice: for stock S2/RS2 .... and ill add mapped as well.

My experience with little over 400hp on the 3071R again didnt have any issues, but ill leave that out, as it is one personal experience and not the rule.

this replacement is for Stock replacement, not tuned cars.

[Thuppu]

But the wire is something like a myth.

Hmm, I don't think so. Maybe it hold for 400++hp if you hit the floor ones here and then..?

[A80Avant]

i am not saying it is not a good deal or anything. But the wire is something like a myth.

if you run a poll in this forum of how many owners have seen a Maf wire being gone on a stock setup, i doubt you get any positive answers. On the other hand, you will get plenty saying that the maf got 'tired' or completely mucked up due to blowby.

if it were me and still using motronic i would definitely go for this change, but TBH, i would immediately go for the high output RS4, even if i was using a stock setup. reason being, its a ready made MAF, you convert once the hoses to fit, and its ready for any future upgrade powerwise.

[s2_wot]

About 700 kg/hr
Needs to be adjustable as well. The plan is to put both MAF's in series and log them to death.

So can we agree that's about 580 m3/h @ 20 deg C?

I'll have a look tonight. I think you'd need a metre of solid duct or pipe either side to make the flow stable for measuring.

[prj]

from what i can remember, the broken wire is very rarely the issue on the stock maf.
I had never had problems with a missing wire esp. on stock turbo/even the 3071. The problem was that either the maf was getting dirty,thus didnt read right, OR the maf itself failed after use to read correctly, but the wire was there.

would the HFM5 have similar issues with oil from the PCV system for example?

Well, that might be your experience... I have seen plenty of broken wires.
Also there are a lot of bad MAF's floating around, and many cars with bad MAF's.
Replacement costs 263 EUR atm, and it is only expected to get higher, or perhaps it will be NLA soon? Who knows.

As for issues - there are millions of turbo cars running on HFM5's. So this would be a question for Bosch, if anything.
Personally, I have not had any problems with the stock MAF, except that mine just quit working one day. There are many that are tired and out of calibration out of 10 years.

With the kit I would sell, a new replacement element would cost 65 EUR, IF it fails.

I mean hey, if you have a better suggestion, I'm all ears.

Can you quantify the maximum airflow you'd expect through the MAF and I'll check out a few suitable in line fans for you.

About 700 kg/hr
Needs to be adjustable as well. The plan is to put both MAF's in series and log them to death.