Hello...

Can someone please shed some light on this dillemma..

I have done tonnes of research and consulted many forums but im going NOWHERE!!

I have a Subaru Version 5 2 door sti Australian delivered.
Has a Apexi power FC specific to the V5 V6 GC8 SERIAL NO PFC GC8F 020

My car came out with the following STOCK AFM or MAF
GREEN LABEL 22794AA010 (this is the stock AFM for a version 5.)

I now want to run an AFM from a version 3/4 Subaru gc8
ORANGE LABEL 22680 AA271.
As im going up in power to about 230kw ATW on E85 and need a STABLE MAF

I dont want to go z32 or Q45

These are the questions i have..

The only real questions i have are...

1. Those who have tried the conversion is it a stable and trustworthy AFM and can it handle is HP level.
2 . Once its wired in properly how do i select the MAF in the power FC?

There are 4 options available when i bring up the page

1.-GC8 Normal
2.-Super Intake
3.-80mm VG30
4.-90mm Vh41
5.-Option

My question is which one do i choose?.. The power Fc is obviously configured for my version 5...
So if i install a v3/V4 orange sticker MAF and CHOOSE OPTION 1.-GC8 Normal will this be ok?

As you know there is no edit button so i dont want to make a mistake..

cheers and thanks in advance..

To answer your questions:
1. No, it will run out of resolution at 350hp (at the flywheel).
2. You can't - it's not a desirable or recommended MAF to use (too small & lacks resoluton).

The Normal GC8 setting is only for the original Version 5/6 MAF, with the factory airbox and snorkus installed and nothing else.

To run a v3/4 MAF you would need to fully map out a custom airflow curve in the power fc on a dyno.......Not worth the time nor the money - considering Apexi has already done the hard work for the Z32 & Q45 airflow/voltage curves already.

Any MAF change will still require a re-tune but the basic airflow curve to suit the Z32 (or Q45) is built into the Power FC, tweaks are needed to allow for airflow changes due to cams/compression etc.


Why the resistance in changing to the proven long-term reliable Bosch (Nissan) MAF's?

Do you have access to a datalogit or other powerfc tuning software, along with a wideband?

Do you understand the maf airflow/voltage scaling in the powerfc and how it effects your maps?

I have a similar set up to you (read my sig below) and I do all of my own modding/tuning/etc.

A Z32 is the way to go, it has better resolution than the Subaru Maf's, is far more reliable & it maxes out somewhere around the 550hp (400kw+) mark.

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[CENTER][SIGPIC][/SIGPIC][/CENTER]
[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

thanks for the reply...

Z32 here we go!

Guys cant for the life of me find a 97 98 wrx airbox lid for my z32 conversion.. Can anyone help..?

If not will the 90mm Q45 MAF be stable and ok for up to abou 230kw ATW as i may plan to go E85.. or is the z32 better resolution and more safe..

Thanks in advance..

I have 232kw at the hubs and have over 35% capacity left in the Z32 maf.

You will have to modify an airbox lid to suit any of the nissan maf's or just run a process west in guard cold air intake...........

__________________
[CENTER][SIGPIC][/SIGPIC][/CENTER]
[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

Thanks rossco...

Will the Q45 MAF do the job? Assuming E85 conversion and 230kw ATW max at the wheels?
Is it a stable MAF ? And good for what Kw ATW ??
or does it suffer from low resolution and power loss at high rpm?

reason being I'd like to keep the car looking stock and with the V5 airbox the Q45 will drop straight in,, and make life a lot easier and cheaper too!!!

Cheers pk