DME Alternatives
 

Hi All

I have an 86 911 3.2 engine (930.20 I think, its a UK spec engine). Previous owner replaced the air box and air flow meter with a MAF and a little electric box that sits between the MAF and the DME.

I've no proof what it is or how it works, but the engine does run. My assumption is the extra ecu is just translating the MAF signal to something the DME recognises (i.e. Translating the MAF signal to look like an AFM signal).

I'm looking to remove it, as its an unknown and if it breaks then I'm stuffed! One option is to put it back to stock, but before I do I thought I'd see what else is out there?

Anyone use an aftermarket ECU with one of these engines? Any other options worth considering?

Total waste of money and time!

Best option!

Another waste of time and money!

There are aftermarket ecu’s that can use a MAF input directly instead of translating to an ‘old’ volume and temp related signal. But if you do go that route, contact me as I am interested in your original Motronic ECU.

Those are easily worth +$750, and are very hard to find.

I know, and for our Belgian MOT you are not allowed to make any changes to the engine injection system or use aftermarket ecu’s. It all needs to stay original...


Sent from my iPad using Tapatalk

They sell for £1000+ on ebay in the UK.

The stock AFM, air box and harness is going to cost £1k.

So I could either pay £1k to go back to stock, or get £1k for selling my DME and buy an aftermarket setup. If that costs less than £2k then I'm quids in!

BTW its not in a 911 any more, so needs a custom intake and has a complete custom exhaust (using a turbo Thomas manifold) etc. So I need a custom loom and it might do well from custom mapping within its new home.

The 3.2 AFM with the barn door and needle over carbon tracks (!) is another charming old school device. It looks an evolution from the CIS air flow plate system for measuring airflow. Hard to see how moving a barn door beats a modern MAF system in terms of response.

Dyno data indicates basically no differences.

I would say that the main problem with the afm is that the track wears. I have two of them and both are worn down to the PCB. Re-tracking helps a little but still ‘jerky’ behaviour when driving slow (parking lots,...) and returning to idle.

Finding a good afm is a game of luck as you cannot inspect them upfront.

I would keep the MAF if nothing is wrong with it and work with a VEMS or so if originality is not needed.


Sent from my iPad using Tapatalk

Sounds like you probably have the MAF unit from a German company DMEshop24.
Check out my thread http://forums.pelicanparts.com/porsche-911-technical-forum/812518-just-installed-maf-intake-kit-my-964-3-6-transplant-motor-simple-awesome.html
I have used this system since 2014 on my 3.6 964 motor and it has been flawless. As you will see in the thread several Pelicans have also opted for the 3.2 version of
the same product. If you have the unit described, the beauty of it is you can remove
the MAF sensor and cable/box and just replug to the original air flow meter and you are back to stock.
My experience with this unit has been great, much better idle and much better
part throttle performance.
If you have a different unit please post a pic, I'd like to see it.
Cheers,
Grant

I've seen many with over 200K miles with no problems! It helps to keep them lubricated, e.g. WD40.

Lubricate the track?

Yes! And lubricate the pivot points of the flap with a light oil.

Same idea (I think) but yours is far better engineered! I'll get a pic next time I'm at the workshop

Yes, I can believe that but how about the response to throttle changes ?

What I have is a "Filmstar" hot film level translator from Milford Microsystems in the UK.

Apparently this is a company that was run by Geoff Everett, formally of the original AMD. Doesn't appear to be operational anymore though.

Afm vs. Maf...
 

If you want a real MAF not a translated AFM then get the kit that was designed and programmed by SAL CARCELLER.
The kit includes a fully refurbished 28 pin DME with code that incorporates input from a state of the art MAF and 6 Bosch 4 hole injectors and a matching cone air filter.
and...most importantly a comprehensive installation instructions and full support from SAL. 401-264.9909/
I got the kit 1n 2017....great results!

elrato -- if this was my car/engine, I'd follow the old adage "if it ain't broke, don't fix it"

-- i.e. if this setup is working fine now and (as clarified above) is is a standalone subsystem that could be easily brought back to stock if it ever were to become an issue, why spend the time/$$$/effort necessary to put something else (that's not necessarily better) in its place?

I've got Sal's modern MAF, modern injectors and DME in my '87 3.4 "Hot Rod." Great system. Did I mention it's modern? The R&D and support are EXCELLENT. No piggyback boxes, extraneous wiring, etc.

I've got stock injection in my '88 "all original car," but tuned by Steve Wong. Also a good setup.

I like keeping my cars closer to stock than non, but there's some things that benefit from more modern technologies, materials, etc. The Sal Carceller system and the KW V3s on my '87 don't look stock, but the increases in drivability, reliability and performance can't be ignored.

I agree with your comments about Sal's system. Problem is the MAF system I have
on my car is on a 3.6 motor. Unfortunately Sal hasn't done the work to engineer his
system for the 3.6 DME, as it is markedly different than the 3.2. But by all means,
if you have a 3.2 Sal's system seems to be "DA bomb".