If you put an aftermarket intake system on your car, what do you do with the AFM? Do you just take it out or what?

 

that depends on the intake setup.



You can't simply ditch the AFM without changing over to a different form of engine management. You could replace the mechanical flapper AFM with something else adapting it to the stock ecu, like a hot wire MAF for instance, but that would be a complex task.



If you wanted to run anything that involves eliminating a air flow meter entirely you need to switch over to speed/density, like the haltech, electromotive, or SDS standalone units.





To just ditch the air box and put a cone filter on you keep the AFM and put the cone right on it.... the AFM is a restriction in the intake so not only does switching to speed/density with programmability help you with tuning capabilities, it also frees up the intake (and simplifies things under the hood)

 

You'll need a filter adapter because the afm is square shaped.

 

u only need the filter adapter if your car is 86 to 88.



model year 89 to 92s have a circular inlet

 

if you have an 86-88 why not UPGRADE to series 5 intake and then UPGRADE your UPGRADE to a cone filter. Thats not ONE UPGRADE but TWO...i shall call it the SUPERDUPPER INTAKE UPGRADE....i dunno just thought about that...

 

pengaru - Thank you! I don't know how many knuckleheads on the "other" forum boldly state that switching over to a hotwire MAF is impossible. The tell me that it can not be done in spite of what is done in Japan. I guess if it's not all over the internet then it must not exist to those tools. This is just what I'll be doing once I get my buddy to ship me a MAF from a Nissan RB20DE (about the same size as a Z32DETT MAF) and I get a GReddy E-Manage from another friend that's going with a standalone.

 

i got a K&N intake with a AFM still on. I dont think you can take it off. Or can you ( the questions of rotary life)

 

it's definitely possible, but surely it will be a complicated task. The stock AFM is a segmented potentiometer, I believe the hotwire MAF's do not operate that way. What I mean is... the stock AFM cycles through it's full resistance range a number of times when opening. I do not remember how many segments there are, but you can pop the cover off and observe the pattern on the circuit board, it's a bunch of black arrows overlapping one another, each arrow represents the full resistance range. The ECU must count the segments as the flapper moves (this is for the S4). I'm guessing this is just a way mazda obtained greater resolution in the flapper without increasing the resistance range (or precision in the metering of voltage).



Once you get that figured out, you also have to make sure they respond the same way to airflow.



If you ask me, it's just not worth the trouble. The stock ECU is not a great system, the original wiring is usually questionable in our cars anyways, wasting alot of time to get a hotwire maf to function properly on a ECU that has little to no documentation and tunability is kindof dumb, if you could use something like LS1Edit with the thing then maybe it would be worthwhile. For all the trouble it will be you might as well just get a standalone that you have a: documentation for and b: control of and c: doesnt require a air flow meter at all.



just my $.02

 

I like a challenge.