Evo Maf Swap

Posted: Fri Apr 21, 2006 1:21 am

Once upon a time there were 1g Mafs....those sucked. Limited to reading airflow to ~30lbs/min.

Next up were the 2g Mafs....much better. Limited to reading airflow to ~42lbs/min.

Finally we have the end all be all Evo Maf. Limited to reading airflow to ~62lbs/min.

62lbs/min generally equals about 600whp. This is more than enough for any DSM still running a Maf after that point I would only recommend a full standalone engine management system using speed density instead of a Maf.

The reasons I decided to run one in my car in replacement of my 3” GM Maf are: Better airflow readings, easier to tune and the air temperature sensor and barometric sensors are still used.

The Evo 8 Maf is an almost direct swap for the 2g! All the pins are the same, but the connector is different and the sensor outlet to the intake pipe is round not oval. You will either need the connector from the Evo your Maf came from or you can use the connector from 01-04 Chrysler Sebring (Cpe), 01-04 Dodge Stratus (Cpe), 00-02 Mitsubishi Eclipse, 03-04 Mitsubishi eclipse exc. GTS, 99-03 Mitsubishi Montero Sport 3.0L, 2003 Mitsubishi Outlander, 99-03 Mitsubishi Galant. Just cut one wire at a time from the stock 2g harness and splice it accordingly to the same pin of the new connector.

The wiring for the Evo connector:

Pin 1: gray wire - Connects to ECU pin 81, which is a 5V source and goes to the volume air sensor's atmospheric pressure sensor.

Pin 2: yellow/blue stripe wire - Connects to ECU pin 85, which appears to be a sink (sort of like a ground for solid state devices). Appears to be the ground for the volume air sensor's atmospheric pressure sensor.

Pin 3: white/red stripe wire - Connects to ECU pin 90. This is a signal pull-up line. Appears to be the actual atmospheric pressure sensor signal to the ECU.

Pin 4: red/yellow stripe wire - MFI relay. This appears to be the main 12V power from the battery when the relay is energized.

Pin 5: black wire - Chassis ground through ECU pin 40.

Pin 6: red/blue stripe wire - Connects to ECU pin 72, which is a 5V voltage source for the intake air temperature sensor in the Maf.

Pin 7: blue/black stripe wire - Connects to ECU pin 19.

The wiring for the 2g connector:

Pin 1: gray / yellow stripe wire - Connects to ECU pin 81.

Pin 2: orange wire - Connects to ECU pin 85.

Pin 3: blue / yellow stripe wire - Connects to ECU pin 90.

Pin 4: red wire - Connects to the MFI relay, cam shaft position sensor, crankshaft position sensor, idle air control motor, and both oxygen sensors. This appears to be the main 12V power from the battery when the relay is energized. This is slightly different from the Evo circuitry because Mitsubishi was still running lots of sensors off the same power source.

Pin 5: black wire - Chassis ground through ECU pin 92. Also goes to the fuel tank differential pressure sensor, the manifold differential pressure sensor, throttle position sensor, engine coolant temperature switch, and both oxygen sensors. This is slightly different from the Evo circuitry because Mitsubishi was still running lots of sensors off the same ground lead.

Pin 6: red / blue stripe wire - Connects to ECU pin 72.

Pin 7: blue/black stripe wire - Connects to ECU pin 19.

Pin 8: Empty - Unused

The wiring for the 1g connector:

Pin 1: - Connects to ECU pin 6.

Pin 2: - Connects to ECU pin 10.

Pin 3: - MFI relay. This appears to be the main 12V power from the battery when the relay is energized.

Pin 4: - Connects to ECU pin 23, which is a 5V source and goes to the volume air sensor's atmospheric pressure sensor.

Pin 5: Empty - Unused

Pin 6: - Chassis ground through ECU pin 17.

Pin 7: - Connects to ECU pin 16, which appears to be a sink (sort of like a ground for solid state devices). Appears to be the ground for the volume air sensor's atmospheric pressure sensor.

Pin 8: - Connects to ECU pin 8, which is a 5V voltage source for the intake air temperature sensor in the Maf.

Now to swap this Maf in to a 1g it is pretty simple. I followed the instructions as per http://www.vfaq.com/mods/2GMAF-1G.html instead of using a 2g Maf like that article is for I was using an Evo Maf, but the pins stay in the same orientation.

The pins to swap/combine are as follows for a 1g to 2g/Evo(keep in mind that the pin number is from the back of the connector where the wires come out of):
1G___2g/Evo
1_______7
2_______3
3_______4
4_______1
6_______5
7_______2
8_______6

1g

2g

Evo

For installing the Evo Maf I could have just used my existing aftermarket intake pipe and a filter adapter w/ filter on the Maf, doing this would end up looking really clean and a lot like a 2g under the hood. This would not do for me, as I am going to be racing in the stock appearing class at the shootout and my intake has to look externally stock for the model year. In order to have the Evo Maf in my stock air canister it took a lot of work but the end does really justify the means. The Evo Maf outlet is identical to the outlet of the 1g air filter canister. In order to get the Evo Maf inside my canister and still use the stock K&N replacement air filter I had to modify both the canister and the Evo Maf.

Stock 1g air filter canister unhacked.

Stock 1g Maf sensor; it is really restrictive and bulky.

Step #1 Remove the stock 1g Maf sensor from the canister backing. Remove the 6 Phillips screws around the outlet and 2 on each side of the female plug.

Step #2 Cut off the metal outlet ring and enlarge the hole if necessary till the Evo Maf outlet fits through the opening.

Like so...

Step #3 Trim the inlet of the Evo Maf down till you are at the radius inlet of the Maf.

If you did a good enough job, the Maf should be able to sit inside the canister with the filter on, like so...

Here you can see how I cut my stock female connector from the stock 1g Maf and soldered the leads right to the corresponding leads.

It looks stock but you and I know its not!

I have this done on my personal daily driver 1991 Eagle Talon Tsi and it runs flawlessly.

Other vehicle Mafs similar to the Evo Maf:
01-04 Chrysler Sebring (Cpe)
01-04 Dodge Stratus(Cpe)
00-02 Mitsubishi Eclipse
03-04 Mitsubishi Eclipse exc. GTS
99-03 Mitsubishi Montero Sport 3.0L
2003 Mitsubishi Outlander
99-03 Mitsubishi Galant
The difference between those Mafs and the Evo Maf is that the air horn inlet is different but the sensor is the same. Hacking the air horn (as seen below) will yield similar/equal flow to the Evo Maf. The best sensors to use are the 399(Evo Maf) or 482 sensors. That number can be found on the top left corner of the sensor tag (as shown in 4th from the bottom picture above).

This is an unmodified Maf from the above listed vehicles...

This is a Maf from the above listed vehicles with the air horn hacked...

Don't forget that you will need some type of tuning software to be able to run the Evo Maf in DSM, because the ecu will think it is still metering with the stock Maf. For a 2g the Evo Maf will make the car run about 15-20% more lean before tuning, 1g's with the Evo Maf will run about 35-40% more lean before tuning.