Lancer MAF Swap Step-by-Step Guide
 

**************************************** WARNING ***********************************
The information in this thread is to be used at your own risk. If you are unfamiliar with the EcuFlash software or how to tune and make changes in EcuFlash you can cause severe damage to your engine. I assume no responsibility for any damage that occurs as a result of improper tuning/flashing of your ECU.

The EcuFlash values shown below are not necessarily the exact values needed for any one person's engine setup. The values shown are from different Mitsubishi vehicles with larger displacement engines and different airflow demands. They are ALL to be used as a baseline by which you can tune your engine with.
**************************************** WARNING ***********************************

The Lancer MAF (mass air flow) sensor is a very restrictive piece that bottlenecks the engine's ability to breathe. By swapping in the MAF sensor from any number of other Mitsubishi vehicles, you can remove the restriction and gain some HP in the process. The following MAF sensors can be swapped into the 4G94 Lancer:

- 501 -

Stock Lancer MAF shown on the left, larger 501 MAF shown on the right:
https://www.evolutionm.net/forums/at...4&d=1249330913

Typically found in Mitsubishi vehicles with a 4G64 engine:

ECLIPSE 00-02 (All trims)
ECLIPSE 03-05 exc. GTS
GALANT 99-03
MONTERO SPORT 99-03 3.0L (6 cyl)
OUTLANDER 03
SEBRING 01-05 (Coupe)
STRATUS 01-05 (Coupe)

This MAF is the most practical swap for a non-turbo Lancer, as the MAF values from the 4G64 ECU are easily adapted to the Lancer's ECU with EcuFlash. This MAF is only rated by Mitsu for 210 liters/second, and has ~.78 psi pressure drop because of the larger airhorn blocking the inlet.

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- 482 -

https://www.evolutionm.net/forums/at...0&d=1249330499

Typically found in newer Mitsubishi vehicles with a 3.0L, 3.5L or 3.8L V6 engine. This MAF flows almost identical to the 399 Evo MAF, ~61lbs/min maximum. This MAF has a pressure drop of ~.54 psi at 240 liters/second. This MAF can be swapped into a non-turbo Lancer, but the values used for the Lancer ECU will be trial and error as this MAF flows almost the same as the Evo MAF and is found on larger V6 Mitsu engines. Turbo'd Lancers will have a better transition to this MAF as they can use either the Eclipse GTS or Evo MAF values as a starting point, depending on the individual setup.

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- 399 -

Found on the 4G63 Evo VIII/IX engine. It is the highest flowing MAF available, flowing a maximum of ~62lbs/min with a pressure drop of ~.526 psi at 240 liters/second. The 399 MAF is pretty much identical to the 482 MAF in both size and airflow. This MAF can be swapped into a non-turbo Lancer, but the values used for the Lancer ECU will be trial and error. Turbo'd Lancers will have a better transition to this MAF as they can use the Evo MAF values as a starting point.

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Now onto the swap itself. All of the MAFs listed above are plug and play. You can unplug and remove your stock MAF, install a larger MAF, plug it in and that's it for the swap. All that's left to do is to use EcuFlash to change the MAF values in your ECU's ROM to reflect the larger MAF.

Here's a rundown on how to change the MAF values in your ECU's ROM with EcuFlash after swapping in a 501 MAF:

-1- Using a Tactrix/OpenPort cable, read your ROM from your ECU in EcuFlash.
-2- After EcuFlash finishes reading your ROM, expand the Fuel category in the left pane to reveal the MAF tables.

The tables you need to modify are: MAF Scaling, MAF Smoothing Table, MAF Sensor Filtering and MAF Size:
https://www.evolutionm.net/forums/at...3&d=1249330522

Here is what the stock Lancer MAF values look like:
https://www.evolutionm.net/forums/at...2&d=1249330513

-3- Using the values for a 2003 Eclipse GS shown here, change your Lancer MAF values to the larger values for the 501 MAF:
https://www.evolutionm.net/forums/at...1&d=1249330505

-4- After you have changed the MAF values in your Lancer ROM to the correct 501 MAF values, save the changes to your ROM (if you have/want a copy of your ROM saved on your computer) and write the values to the Lancer ECU.

-5- From here you will need to do some datalogging and tuning to get your Lancer dialed in properly.

Those wanting to perform a 482 MAF swap on a non-turbo Lancer, you can use the values shown here, from a 2005 Eclipse GTS, as a starting point for your Lancer's ROM:
https://www.evolutionm.net/forums/at...9&d=1249332538

You can see that the values for the 482 MAF are sort of in between the values for the 2.4L 4-cylinder non-turbo 501 4G64 Eclipse MAF and the 2.0L 4-cylinder turbo'd 399 Evo MAF. To get this MAF to work on a non-turbo Lancer, proper datalogging and tuning will be required to adapt it to your individual engine setup.

Those with turbo'd Lancers performing this swap will see an easier transition as the HP rating and airflow of the engine the 482 MAF came from is pretty similar to that of a turbo'd Lancer.

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If your Lancer is turbo'd and you are opting to swap to an Evo 399 MAF, you can use the values from a 2003 Evo, shown below, as a starting point for your Lancer's ROM:
https://www.evolutionm.net/forums/at...5&d=1249331594

Values shown above for the 482 MAF can also be used as a starting point for Lancers if the Evo's 399 MAF values gives your engine idling issues.

Same steps and changes in EcuFlash apply for this MAF swap.

Big thanks to darkmitsu for all his help with this writeup. Additional reference pulled from the following sites:
http://wnydsm.seelbinder.org/viewtop...a7ec78802486a2
http://www.galantvr4.org/ubbthreads/...fpart=all&vc=1
http://www.dsmtalk.com/forums/showthread.php?t=202358

-reserved-

Thanks you're the man!
lol

Need to sticky this in the how to forum.

Can't wait to try this out. I'm still working with someone to get an EVO maf

thanks, looks beat though... :lol:

lol Yup
Also sellers feedback isn't that great .

would you suggest a 501 or 482/399 for turbo lancers? Seems either or would work just fine if tuned properly. But I don't plan on pushing more than 9psi. Just want to be sure

Well a 501 would be more than enough for 9psi. It would also be a simpler swap in terms of tuning because the values are pretty straightforward.

awesome! thanks for the input!

got my 399 in today {thumbup}

So any dif between a 8 and 9 evo maf?

it uses the same MAF, but i believe it is tuned differently. Such as MAF scaling, smoothing table, etc.

I got mine off a IX