Just been debating lately putting two AFM's in with my twin intake, and jacking in the second signal out put into the first AFM's output to allow a better metering of the intake air so as help low speed metering. Would this actually work by doubling the signal (more or less) seen by the ECU? I'm thinking it might not double the signal but just average it (unless if connected in series), but am looking for ways to make this work if anyone has them?Cheers
you may want to give geoff grisby => a call. i know he has a twin intake however i dono if he has 2 AFM's.... btw... has he sold his car yet? he told me he was but that was a while agoCheres,Red Z.
As far as I know... you MUST use something like an AFC to combine signals from 2 AFMs. You cant just wire it together as the voltages dont correspond to airflow in any sort of linear relationship. The AFC checks one signal, looks up its airflow reading, checks the other signal and looks up its airflow reading, combines airflows then creates a new voltage based on that. Cant see how it would work without one.
Hey DUB>>> How's it going? I have a twin intake with only 1 air flow meter and don't have any low speed problems at all. Do you have some sort of low speed driveability kit installed? I've just blocked off where the IAV use to take it's air from and ran a hose down to my intake and using a T-piece the IAV now takes half it's air from each side of the intake.Cheers, Matt
you could do this >> connect the outputs of each AFM in series and then through an average circuit, something like this maybeAFM 1 Ground --> GND (on AFM connector) AFM 1 Signal --> AFM 2 Ground AFM 2 Signal --> R1 --> R2 --> AFM 2 GroundThe point between the two resistors R1 and R2 is the SIGNAL (on AFM connector) wire. R1 must be the same as R2 and make them small (4.7 Ohm) to reduce the voltage drop across them otherwise you may need an amplifier to compensate for that drop.I have never tried this but it may work and does the same job as the Apexi AFC averaging circuit.
has anyone..-> done any tests or have any data of AFM voltage Vs airflow?? i would be very interested in it Cheers DSZX
Schematic... Originally from z-car.net so credits to Maciek (Z Viking) Cheers [image]http://home.swiftdsl.com.au/~evan/images/aat.jpg[/image]
american site with info i am looking at the same thing.. but apparently its only usefull at 600hp... but there is a site in the states that details alot of DIY technical stuff and i shows you have to do a twin AFM install.. although you need to mod your ECU with a program to take 2 sensors... here is the site.. http://www.ttzd.com/tech/twinpop/twinpop.html good luck
Not installed yet, just looking at the whole picture before I put my twin POP in. Never realised the AIV would have to be modded so I'm already ahead there which is always a great idea cos asking questions halfway thru a conversion always gets my keyboard greasy Cheers
That looks like it could work Had a conversation with Phil (BlackZ) on last saturdays cruise regarding this and he suggested some diodes either side of a feed to the ECU which would help average the signal.
I understand everything on those except for the triangle thing:?)Great to know it's been done before, and thanks for pointing it out Ev. Cheers
