This is a discussion on maf hack questions? within the Tuning: Electronic Engine Management forums, part of the Tech & Modifying & General Repairs category; hi guys so last night i was monitoring my car just gone for a drive the car was pulling like ...
hi guys so last night i was monitoring my car just gone for a drive the car was pulling like never before reason being that i finally got everything on the tune right eg no knock, iam is stable, good afrs etc etc
so i did a wot in 3rd for ****s and gigs and geuss what my maf maxed out cel came on maf sensor to high and it hit the 300 g/s 4.72v limit and when it did my afrs got suddnly droped after 6000 from 10.9 - 9.9 at 20psi so now i have to do the maf hack but theres not much info about thisn and yes i have read the thread on the maf hack but i still got a few qeustions
- would i benifit on this hack with a aps 65mm intake or do i need a bigger maf housing? (btw the whole maf has been rescaled)
- what excatly do i multiply my values by 0.5
maf scailing
injector scailing and latency
afr learning
i know theres more but can someone point em out?
- do i need too raise/change the voltage on the maf scaling? i know the max is 5v but mine is set at 4.72v
- when halving the maf values is there quicer way of doing it? or do i have too half each cell individually?
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2005 WRX STi (Mods | Virtual Dyno)
Resident Tuner @ WTF Tuning, LLC
"Never trust anything that bleeds for a week and lives ..."
UNYSOC
That thread answers every single one of your questions. Especially the very first post. I would read it again. Look at the value in red. It should be painfully obvious the G/S was changed and not voltage. This is in the very first post.
"As you can see, at 4.96V we're only at 176g/sec. We could effectively increase this to 300g/sec if a bigger MAF housing is fitted. And since we've cut all values by half, this would actually correspond to 600g/sec true value."
If you don't understand exactly whats happening then I don't suggest doing this. You need to slow down and actually absorb the info instead of just briefly skimming it. You half the G/S not the voltage,in the MAF scaling. Any table that has a load reference you need to change. Obviously the timing tables. There are also several tables that have yet to be defined in Romraider/Ecuflash that probably reference load. So this "hack" isn't 100%.
NASIOC - View Single Post - 300g/s workaround - 'hacked' MAF up to 600g/sec or 1200g/sec
http://www.romraider.com/forum/viewt...ilit=maf+limit
Also I remember from somewhere there are a few JDM 2.0L 16bit ECU STI's whose MAF scaler is hard coded to 400 g/s instead of the 300 g/s. The G/S are set at 300 g/s in the ROM's just like the 32 bit ECU's but the ROM will allow you to change the value to 400 g/s. Or you can just us the Groupe-N ROM (Carberry) and just run speed density and ditch the MAF altogether. No massive value change needed.
Last edited by Donkey; 10-11-2012 at 06:40 AM.
you can't just half maf alone, you gotta half the scalars in your timing tables and afr tables and injector scalar and you would still have the same issue (if you are maxing out to 5v), you need a bigger maf housing.
ive done everything i could for the maf hack went to put the tunee on started it up and then car had lumpy idle sounded cammed my afrs were at 22.4 wouldnt let me rev nothing ill upload the map onto rom raider and if its alright can use tell me what im missing i halved everything under engine load etc etc
RomRaider • View topic - trynnna do the maf hack
https://docs.google.com/spreadsheet/...CUFRVYUE#gid=0
here is a log of my car maxing out
He's talking MAFv, not MAF (g/s). You're only hitting 4.72VOriginally Posted by sxcrxy
2005 WRX STi (Mods | Virtual Dyno)
Resident Tuner @ WTF Tuning, LLC
"Never trust anything that bleeds for a week and lives ..."
UNYSOC
You're not maxing MAFv. Do the MAF hack and you should be fine.Originally Posted by sxcrxy
2005 WRX STi (Mods | Virtual Dyno)
Resident Tuner @ WTF Tuning, LLC
"Never trust anything that bleeds for a week and lives ..."
UNYSOC
Yes. Rescale the MAF voltage up to 4.96v to utilize the whole range of the sensor and change the CEL value. I apologize. You asked this in your first post And I told you to just change the G/S not realizing you were hitting the CEL/DTC limit.This info should have been contained in the link EJ257 first gave you. Look at the very first post in the thread at his entire MAF scaling that is shown in the code box. It's much faster and easier to rescale the MAF in Ecuflash than it is Romraider.
Last edited by Donkey; 10-15-2012 at 05:01 AM.
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