Could someone one design a quick MAF replace kit... I had one die, there was no real warning.

I think the car seemed to "cut out" a little now and then before it happened... not sure... it seems to be doing it again now.

I have a GT600 kit, including the "fancy" air box from EVO. Should I go back to the stock Air box?

Wasn't there and upgrade to a mitsubishi MAF coming out?

Thanks,
Seth.

 

What do you mean by MAF replace kit? Just carry a spare MAF. They are very easy to change out. When you blow a MAF, you typically get ABS/PCM lights and then a CEL. Perhaps your plugs are bad. Some claim cleaning the MAF works.

I removed my V-flow and have not blown a MAF since, but that is not always the case (just did not work for me at my altitude and hp). The long awaited MIT MAF is still not out (that I know of). Other tuners have other remedies (Protomotive and UMW).

 

I was mostly being a smart-***.

What causes these things to fail, I've heard turbulance, I've heard EVO air boxes... I also heard there was a solution... but I can't figure out what that solution is.

Seth.

 

Part of the problem is that no one seems to know exactly why they fail. Our MAFs are essentialy a thin film temperature sensor printed on the upstream side, and one on the downstream side. A heater is integrated in the center of the membrane which maintains a constant temperature similar to the hot-wire approach. Without any airflow, the temperature profile across the membrane is uniform. When air flows across the membrane, the upstream side cools differently than the downstream side. As air flows across it, it cools down. The heated film is a positive temperature coefficient (ptc) resistor. This means that it's resistance drops when it's temperature drops. The drop in resistance allows more current to flow through it in order to maintain the programmed temperature. This current is changed to a frequency or a voltage which is sent to the ECU and interpreted as air flow. Adjustments for air temperature and humidity are taken into consideration since they also affect the temperature of the heated film. The ECU then acts accordongly (timing, fuel mix, etc.).

So there are theories that foreign substances may contaminate the film and cause failure (as example, oil on filters). Also that higher hp cars may challenge the amount of air flow and thus spike the current. Several theories no real answer. The proposed solutions , I believe, are to increase the current capacity of the MAF or put it in a different locations or others?.

 

I think a solution like this would work great:

http://www.maftpro.com/vstinfo.shtml

This is a VERY popular mod for the DSM Turbo guys. Allows to use a HUGE GM MAF that only costs around $40! Im suprised know one has come out with a solution yet

 

Agreed. We also used to use the HKS VPC which had no MAF at all and just a small sensor in the airstream:

"The VPC converts both air flow meter and air mass sensor systems to what is referred to as speed density systems by utilizing a 16 bit central processing unit reading its own intake air temperature sensor and absolute pressure transducer (B-MAP sensor) signals."

It'd be nice to have an option like this for the TT...

 

Yes, a speed density system would be great as well! I ran the VPC on my DSM too. I sent out a email asking the guys at MAFTPRO if they had any interest in making something for our P-cars. I would think all the box is doing is converting the voltage?

 

I know Evoms is working hard on a fix... there are other tuners that have figured this out already... I have one.
good luck,
markski

 

Markski, is it in the programming itself or is there a converter that is used?

 

Maybe Protomotive should create a kit. We can't all afford to send the car there for work.

In the meantime I'm going to get rid of my Evo intake and see if it helps.

Some are using a Boxster MAF with great results. Just pops right in.

 

Seth,

so you have a stage 4 or gt640? A new maf is coming any day now

Jag

 

here is the technical answer...
The stock MAF makes it's peak voltage at 1400 kgs/hr, or 51.33
lbs/min, and at 10hp/lb/min, that's 513hp max. But those engine's don't
make that efficiency, so maybe 490 or so hp, they're pegged.
Now, the input voltage is 12v, so the thing keeps making more output
voltage, but the ecu has a diode clamp on it to keep it from exceeding that
voltage, so the thing just keeps drawing more and more current till it pops.

 

I have a stage 4. I think I'm going to move it up a notch to the 640 here. Are you in the Seattle Area?

Thanks,
Seth.

 

Im in Seattle.

 

Contact Rob at S Car Go Racing. He has converted a few already. I understand it costs about 1K.

The problem is not the EVOMS air intake. It is the fact the stock Bosch MAF is rated to handle less than 500 hp worth of air. Yes, their is a fudge factor, but the fact is after that your stock MAF is living on borrowed time.