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Discussion Starter #1
HEY GUYS,
will a porsche 964 /911 motronic airflow meter work with the L-Jet ECU?
p/n 0280203023 superceeded to 0986280026-904 airflow meter.

PLEASE help me:eek:
 

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Probably not as the L Jetronic system operates at a higher voltage and the Motronic AFMs work with a regulated 5 volts. Tooner was looking quite closely at the swap-ability of larger AFMs from the Motronic systems, have search.

You may be able to raid the circuit board and wiper arm from the L Jetronic put it into the larger Porsche spec AFM housing.
That would sort out the electrical compatablity, but the signal would be wrong as the same amount of air flowing through a larger hole will open the door less. You may be able to play with spring tension, but.........
 

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what are you trying to do? get a bigger afm in there?

if thats it, since you seem like a pretty hands on guy, save the pennies and get your car megasquirt 1. get rid of the afm all together. iv got all the info and a list of everything to build one for the alfa v6, and since you build it out of the car, installing it [the MS1 and a wideband O2 sensor] only take about 30minutes of down time.
 

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HEY GUYS,
will a porsche 964 /911 motronic airflow meter work with the L-Jet ECU?
p/n 0280203023 superceeded to 0986280026-904 airflow meter.

PLEASE help me
This question is so old, noone even bothers to acknowledge it. 2 minutes of your time searching this or the older gtv6.org or even the Milano Resource sites would have answered your question and any other curiosities.

The short answer? No.

However...
 

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Discussion Starter #6
This question is so old, noone even bothers to acknowledge it. 2 minutes of your time searching this or the older gtv6.org or even the Milano Resource sites would have answered your question and any other curiosities.

The short answer? No.

However...
thanks, not too be a pain but why?? the plug is the same as my 75
is it the pluse or voltage, what.
 

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Jazig really has hit the nail on the head. By the time you buy the bigger AFM and get some sort of controller to sort everything out (rare because of the operating voltage above 5 volts. That equals limited market, that means higher $'s. And 'NO' it won't just be a matter of playing with spring AFM tension), then you really are well into the realm of a Megasquirt set up and you still have the limited tunability of just simply fudging AFM voltage signal to the ancient, analogue ECU.
 

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the plug is the same as my 75
Motronic plug not the same as L-Jet (4-PIN vs 7-PIN)

Duk had mentioned it before, you can swap a couple/three parts and use the bigger housing. I have a thread on this somewhere. Without performance cams, raised RPM threshold, and headwork, you will sacrifice every day drivability for a couple horse on paper above 5ooo rpm.

I'd say focus on making it run purrfect with what you have. You can't build a cathedral to lofty heights without first laying a strong foundation my friend.

If the plug is indeed the same, then you have a twin-spark with Motronic already - not L-Jet. Give it a shot and see how it goes. I forget they produced (offered) the 75 in Europe and elsewhere for a few years later than in NA.
 

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Discussion Starter #9
thanks guys for the heads up .But well I won the bid on ebay so it should be
here next week.
it form a Porsche 911 964 3.6 L motronic engine .
is the beemer airflow meter the seam as big as the 75 Potenziata 3.0LT motronic one?
 

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is the beemer airflow meter the seam as big as the 75 Potenziata 3.0LT motronic one?
The Motronic AFM was the same size as the ones used in the old EFI XE/XF Falcon's. Not very big at all.
 

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doesnt matter on the size to much, its better to have a afm with a greater resolution MAPS.

im just going to take a guess but is the stock afm 80mm ?? possibly 90mm ?


also with the 5 and 7 pins that doesn't really matter to often, beleive it or not but there is only like 3/4 wires that are used and the rest are noting.


also shane can you show me pics of the two afm's ?
 

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doesnt matter on the size to much, its better to have a afm with a greater resolution MAPS.

im just going to take a guess but is the stock afm 80mm ?? possibly 90mm ?
Ah, no.
X-number of litres per minute throught the AFM equals Y degrees of flap angle and that equals Y voltage output.
A higher X number = a higher Y number. But there is a point where the AFM will still have travel but won't open any further because the air just isn't dense enough to push that last little bit.

And ye olde vane/flap AFM have square or rectangular passages and are poxy-small. The XE/XF Falcon 1 I have, which measured the same as my old Motronic 1 measures 51mm x 46mm = 2326mm square. That enlarges into a 65mm round hole is 3318mm square. But the whole shooting match can only flow as well as the worst flowing component/area.
 

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That shows you how much i know about alfa air flow meters, i didnt even know they had a flap afm, i was going on hot wire afm's in nissans.
 

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Discussion Starter #14
So I'm going down the road be it slowy of making my 2.5 into a 2.7 with the guts from
a 3.0, with greg gordon supercharger kit .
Would it be better to just fit EMS or sume think like that.
I would like to keep my block number so all the number match the rego papers.
 

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The secret to all force fed engine survival is always control of air/fuel ratios and ignition timing in any combination of engine speed, load and inlet air temperature. So 'Yes' an after market computer is a very good idea, so long as it is consistent and repeatable (not all are as good as they should be) and well tuned to suit your engine.
 
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