PDA

View Full Version : maf



kares_leni
18-08-2011, 10:11 PM
hi I WANT TO UPGRADE my maf do somebody know which one is suitable for our cars maybe Evo6, 3000gt,nissan 300zx ?

Nutter_John
18-08-2011, 10:14 PM
Why do you want to upgrade your maf ?

and no other one is a direct swap

alan
19-08-2011, 03:20 PM
has anyone ever dissasembled the maf and seen who the actuall working part is made by?

Mark 4
19-08-2011, 06:49 PM
Ask Kenneth.

wintertidenz
20-08-2011, 12:01 AM
If you want to upgrade the MAF, just go the whole way and convert to MAP with an aftermarket ECU.

Subaru ETA
20-08-2011, 09:00 AM
I know Kenneth was looking into using a LS1 MAF ages ago

kares_leni
20-08-2011, 06:21 PM
do somebody know what happened with Kenneth,s trying about LS 1 maf ? 10x

Nutter_John
20-08-2011, 07:34 PM
The ls1 needs a convertor and mapping for it to work , it is not a straight forward swap

Kenneth
20-08-2011, 10:47 PM
As per the other thread, I had it working fine just not installed in the car due the the ability to modify the ECUs (made it redundant).

At this stage, I would be willing to try our standard MAF in blow-through mode.

Kenneth
20-08-2011, 10:56 PM
Um, to follow on from that last post... It appears that the MAF we use is actually, at heart, a hot-wire MAF. No *#&%, I kid you not.

After disassembling one, I couldn't work out how it operated until I looked at it in better light. The thin wires across 2 large terminals and some black heat marks on the plastic and I was left thinking WTF?

I am not sure what earlier MAFs did or how they worked, but these are based on hot wire technology.

I ASSUME that it still uses the Karman vortex principle to pulse air over the hot wire to induce a frequency. The pressure holes are in the right place (inlet on the high pressure side, outlet in low pressure) to achieve this.

As such, any air moving through the MAF is going to result in pressure differential which will drive the MAF.

Mark 4
20-08-2011, 11:06 PM
Told ya.

ILLEGAL
21-08-2011, 01:34 AM
I just hate having to find the room to run the damn air flow meters. always been the worst part of any of the turbo swaps iv done. id much rather work on a map based ecu. other than the room they take up i think the kvf air flow meters are the safest way to run fuel injection.. as it automatically takes into account haro pressure air temp and every ounce of air that gos thru it and will normally hit cut point before a lean situation becomes a problem.

scott.mohekey
21-08-2011, 01:52 AM
At this stage, I would be willing to try our standard MAF in blow-through mode.

What sort of benefit does this give Kenneth? I imagine it would allow us to use VTA BOVs, but what else would it do?


Um, to follow on from that last post... It appears that the MAF we use is actually, at heart, a hot-wire MAF. No *#&%, I kid you not.

Is this a good thing?

ILLEGAL
21-08-2011, 02:16 AM
it will let you run VTA BOV, only if the valve is plumbed before the AFM otherwise no diff to the original setup.. it will also let you run a "dose pipe" off the front of the turbos and will increase the sound from the turbos.... it will also help with a huge turbo swap allowing you to mount the AFM in the intercooler piping where theres more room than infront of the turbo (depending on how you mounted it). but im not 100% convinced that our AFM can run like this reliable. better off spending time and energy on getting a map translator up and running for the factory ecu... mapecu seems to run fine on my car aslong as you keep the idle above 1000rpm.

Kenneth
21-08-2011, 02:16 AM
At this stage, I would be willing to try our standard MAF in blow-through mode.
What sort of benefit does this give Kenneth? I imagine it would allow us to use VTA BOVs, but what else would it do?

That is one of the benefits

VTA BOV without having to adjust the spring so tight you get surging when ever so slightly backing off the gas under boost
IAT is in charge air so IAT adjustment is done on ACTUAL intake air temp
Higher air density means the MAF can flow more before being a restriction
Allow the use of Pod filters without worrying about the frequency issues

Down sides:

Increased temperature - not sure how the MAF will cope
Not sure at what pressure it will start having issues with the seals (it IS sealed though!)
Might not give quite the same frequncy response for a given air volume. This would need testing and opens a can of worms if it varies due to increased air density.
You need to stabilise the air for the MAF still, but it will be in the charge piping somewhere.





Um, to follow on from that last post... It appears that the MAF we use is actually, at heart, a hot-wire MAF. No *#&%, I kid you not.
Is this a good thing?
To some degree, neither good nor bad. Interesting though :) It does at least answer the question of why Mitsi didn't go to hot wire technology... They obviously did. Perhaps they didn't want to change their code base or perhaps they just think KVF is a superior way to deliver a load signal to the ECU.

Reconstructor
21-08-2011, 07:59 AM
I am not sure what earlier MAFs did or how they worked, but these are based on hot wire technology.

I ASSUME that it still uses the Karman vortex principle to pulse air over the hot wire to induce a frequency. The pressure holes are in the right place (inlet on the high pressure side, outlet in low pressure) to achieve this.

Hi, Kenneth
Keep in mind, that this is a combined sensor. Besides mass of the airflow it also measures intake air temperature. So, I assume that what You have observed is the temperature sensor, not airflow.

Kenneth
21-08-2011, 10:07 AM
Hi Grigory

No, I am not talking about the air temperature sensor. That looks like a diode and sits behind the measurement apparatus. This can be observed easily without disassembling the air flow sensor.
I am talking about the pressure chambers (one each side) which are used to measure the Karman Vortex street. To view this, you need to take apart (and most probably break, as I have) the air flow sensor.




Hi, Kenneth
Keep in mind, that this is a combined sensor. Besides mass of the airflow it also measures intake air temperature. So, I assume that what You have observed is the temperature sensor, not airflow.

Reconstructor
21-08-2011, 02:09 PM
Sounds interesting. :) Why not posting some pictures on this issue?