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Old 10-07-2007, 05:35 PM   #21
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Well, as I said, do you know how to spec out a microprocessor with the right features (digital-to-anolog and vice versa controllers), have it mounted to a circuit board, spec out some EEPROM chips to hold the code you're about to write, a development kit that includes some sort of sync cable to attach to the port you spec'd on your circuit board so you can transfer code and bench-test the board, write and compile code to tie it all together?

If so, then you'd more than likely not have even asked for wiring diagrams. That's the least of your worries. Ever seen a circuit board schematic?
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Old 10-07-2007, 05:37 PM   #22
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This guy makes magna look like Shakespeare.
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Old 10-07-2007, 05:41 PM   #23
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This guy makes magna look like Shakespeare.
Yeah i suck less
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Old 10-07-2007, 05:49 PM   #24
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Originally Posted by madmalc View Post
hi everyone i want rid of the masive 1.6 mechanical air flow meter and replace it with a 1.8 item can this be done as the 1.6 has a couple more wires than the 1.8 at the minute im only using the hks piggy back ecu any help would be great
thansk malc

my question is.: what HKS piggy are you speaking of? the VPC? Then it should be running off a MAP sensor and AIT sensor and the AFM isn't even a requirement anymore.
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Old 10-07-2007, 07:54 PM   #25
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look matey sum how i doubt it is out my leauge i do everything from mot's n service to ecu mapping i know wat im doing and if i put my mind to it could figure it out myself just thought that someone on here would of already had the same idea and of done the hard work so to speak

thanks for the help ill put a how too up in a couple of days to prove a point
I wish you the very best of luck and hope you come back and prove me wrong.

But let's be realistic. Unless you're a mechnic/EE/CE, you don't have a snowball's chance in hell. So more likely, we'll just never hear from you again.
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Old 10-08-2007, 09:09 AM   #26
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I wish you the very best of luck and hope you come back and prove me wrong.

But let's be realistic. Unless you're a mechnic/EE/CE, you don't have a snowball's chance in hell. So more likely, we'll just never hear from you again.
you clearly think you know what you are talking about but you know naff all get a life i was asking for ideas and posotive input on the matter not a load of abuse about mirco processors and chips


for those of you who were trying to point me in the right direction (magnamx5) im very greatfull i will post up how to do it ina couple of days

malc
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Old 10-08-2007, 09:38 AM   #27
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for those of you who were trying to point me in the right direction (magnamx5) im very greatfull i will post up how to do it ina couple of days

malc
we'll be waiting patiently.





I also want to reminder you that a maroon username = moderator.
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Old 10-08-2007, 09:39 AM   #28
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But you will need 4.5 volts at WOT and .4 at idle. As far as i can tell there is no C+ mapping or code required this is a simple inversion of the voltage signal.
are you sure it's a linear inversion? has anyone done the testing to verify this?
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Old 10-08-2007, 09:43 AM   #29
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As far as i can tell it is the afm is just a potentiometer. i have never built or considered the circiut but from what i can see in the diagram and explanation it seems that is it linear. And the RX7 info posted earlier by brian states the same. http://howto.globalvicinity.com/gv_w...=120&co=1&vi=1
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Old 10-08-2007, 09:44 AM   #30
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Originally Posted by madmalc View Post
you clearly think you know what you are talking about but you know naff all get a life i was asking for ideas and posotive input on the matter not a load of abuse about mirco processors and chips


for those of you who were trying to point me in the right direction (magnamx5) im very greatfull i will post up how to do it ina couple of days

malc
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Old 10-08-2007, 09:48 AM   #31
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and that is for an rx-7 AFM vs a ford MAF. are you referring to this image? the one with the caption, "The very nonlinear AFM vs. MAF plot."?

http://www.globalvicinity.com/images....2489_4690.jpg

the relationship for a 1.6 AFM and a 1.8 MAF would, i imagine, be different from the rx-7 vs ford relationship...
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Old 10-08-2007, 10:13 AM   #32
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are you sure it's a linear inversion? has anyone done the testing to verify this?
Dude, have you been listening/reading this thread or the link I posted at all? Crack open a Miata/RX-7 shop manual if you'd like to read more on the AFMs they use.
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Old 10-08-2007, 10:20 AM   #33
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and that is for an rx-7 AFM vs a ford MAF. are you referring to this image? the one with the caption, "The very nonlinear AFM vs. MAF plot."?

http://www.globalvicinity.com/images....2489_4690.jpg

the relationship for a 1.6 AFM and a 1.8 MAF would, i imagine, be different from the rx-7 vs ford relationship...
No, the relationship is exactly the same. The RX-7 and Miata AFMs are basically the same, volume-measuring flow meter that read from 4.5-0V, from min to max airflow. The Ford and Miata MAF are basically the same, mass-measuring flow meter that output from 0-5V from min to max airflow.

So, you're pretty much looking at the same, inverse relationship. The numbers obviously won't be exactly the same as the RX-7 vs. Ford, but the procedure for arriving at the end result is identical.
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Old 10-08-2007, 11:22 AM   #34
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posting to subscribe 2 this thread i hateed look of the trap door 'AFM' too so ugly and out of place i have always loved look of the 94+ MAFs!! damn i wish ne1 thought of doing this swap before i did standalone that have saved me soooo much money but i'm no mechanic and dont no ecu maping so even if i did think of it i couldnt figure it out damn **** ******

let me no how it does

HKS FTW!!!!
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Old 10-08-2007, 12:51 PM   #35
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Where's Lazzer when we need him...

Yes, one difference between the MAF and the AFM is that the airflow-voltage curves are inverted. And that could be solved with a single op-amp.

However if you invert one of them and then plot the curves of the two devices on a flowbench, you'll find that they are not the equal. My observations of the 1.6 AFM indicate that it is non-linear, and I'd imagine that the 1.8 MAF has some surprises as well.

That page describing the conversion was pretty, but bordering on useless. The author simply glosses over some key subjects like "The easiest way to do this is to fix the intake air temperature and atmospheric pressure sensors at constant values of our choosing" and "After constructing the translation circuit..." without actually describing the circuits involved. It's obvious that they have constructed a working version of the circuit as they have the logs to prove it, but without providing a schematic the whole thing is academic.

I guess what it comes down to is this- why bother transplanting a 1.8 MAF onto a 1.6 car when you can simply remove the air metering device altogether. Both Megasquirt and EMU have the ability to do this, and the exact steps necessary have been fully documented in detail for both systems.
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Old 10-08-2007, 01:01 PM   #36
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Originally Posted by madmalc View Post
look matey sum how i doubt it is out my leauge i do everything from mot's n service to ecu mapping i know wat im doing and if i put my mind to it could figure it out myself just thought that someone on here would of already had the same idea and of done the hard work so to speak
Geezus! can you please use some punctuations? I understand you may be writing from the other side of the pond, but still! Last I checked, Brits used commas and periods.

(or better yet, just stop replying to this thread)
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Old 10-08-2007, 01:44 PM   #37
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So, you're pretty much looking at the same, inverse relationship. The numbers obviously won't be exactly the same as the RX-7 vs. Ford, but the procedure for arriving at the end result is identical.
the procedure for arriving at the end result is certainly identical. as you stated the voltage relationship may be similar, but one still has to go through mapping the signals in order to find that relationship.

my argument is that this relationship is not a simple linear inversion. whoever decides they want to go through the trouble cannot just 'flip' the MAF voltage output to simulate the AFM voltage. The voltage needs to be fed through a nonlinear equation or look-up table.

after that is done, said (crazy) person has to fix the voltages for IAT and pressure in order to maintain the validity of the mapping.

in the end, i agree with others that going this route is pretty pointless. if the OP finds the afm ugly, then i personally think he should simply convert to MS and run a MAP based system.
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Old 10-08-2007, 02:28 PM   #38
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Precisely.
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