MAF scaling.
 

Hello.
Been reading a couple of threads on here relating to MAF scaling where a person has been advised to have the MAF re scaled after having an induction kit fitted.
I've searched high and low and can find out lots of info on how to do it but when is it really needed?
Is a MAF re scale only required if the pipe the MAF sits in is increased in size?
If I were to fit an induction kit that had the same internal diameter as a standard MAF housing would it need to be re scaled?
Thanks in advance.

Anybody got any input on this?
Cheers Ian.

I thought only a mapper could re scale a maf sensor but I could be wrong.

Hi Ian,
If you had put this in the "Mapping" forum you may have had a quicker response. :)

A MAF rescale is normally required when you alter the flow of air around the MAF sensor, i.e. if you enlarge the pipe diameter. You may also need to rescale the MAF when you get close to the current MAF scale limit.

You *should* be OK if you replace like for like, but this can't be gauranteed. It's not just the diameter of the pipe, but also the location of the MAF sensor and actual air intake that can affect the overall MAP, say for instance on the fueling side.

It's probably worth having a chat with one of the mappers on here, explaining what you are altering from and to and I'm sure they will be able to offer advice on whether a "check" or "map change" would be advised. :)

Done as part of mapping, often even on standard air box.

If its not on an induction kit it needs a remap anyway

Interesting you say that. When I did a load of testing on my SPEC C (all the original Stage 1 work), the OEM box was taken off and a RCM kit (not big MAF) was put on. No issues that required a remap when we did road and dyno testing.

But you checked it

Of course, but the checking bit wasn't the "interest".... it was your comment about "needs a remap anyway". :)

imho 99% of cars fitted with decat and induction will need mapping..

Btw this should be in the mapping section !
There's been a lot of talk about remaps when fitting an induction kit and I must stress in (my experience and my car ) I've tried 2 or 3 induction setups and none had a massive effect ( not enough to warrant a remap )
Like I've said on loads if posts bug ecus can make adjustments to compensate for slight changes
I only had inlet sizes comparable with the standard maf diameter not a larger diameter ( if your going larger you're probably using a bigger turbo so are gonna be looking at mapping anyway )
It's interesting Simon (jgm) you said 99% need a remap for an induction and decat , I do agree with that , but for just an induction I don't
I think it should be clarified , IMHO fitting an induction kit is not gonna blow you're car up , no more than a ( vta dv) but you're not gonna get any gains without a remap and the reason the maf scale has to be checked when mapping is that due to the other perameters you have to change you need to know the base you're starting with is solid / and within the range that's expected in order to keep all the other perameters in line when mapping
To the op , there are plenty of maf scaling tools on romraider , for interpolating , spread sheets ect , if you're going to go down this route you're going to need the cable , software that you will need for mapping and if you have the interest in scaling you're maf , maybe you should look into diy mapping you're car If you're ecu supports it

Tony

VERY dangerous comments Tony - I 100% agree with Simon and from my experience also there is a need to re-examine the fueling on almost all cars. Sometimes the issues extend into boost control or ignition timing too.... Any or all of these could lead to VERY expensive rebuilds for the owners of the cars.

People reading your post may get the impression that you have some wider experience than just tinkering blindly with your car or those of a couple of mates. :nono:

So in response to the initial question despite it being in the wrong section would it need to be remapped if the diameter stayed the same, and if so why?
Thanks Ian

yes it would..

the air flow through the maf will be different due to the freer flowing filter

+ 1

or the shape of the induction trumpet will affect the flow through the filter at different rates depending on the level / rate of flow.

+1 lol

lol

To Simon and Duncan , I fail to see how an of the shelf induction will alter fueling ,timing and boost to an extent it could cause potential engine damage ,
I would be interested to see some evidence of this ,
Just a standard I,e k&n kit , with no other mods , back to back data would be nice
And as I usually say I'll then shut my gob and crawl back into my hole

Tony

https://www.scoobynet.com/general-te...-good-bad.html

heres a thread in which posted my findings of an induction set up when i first started to dabble with mapping
i know its only cosed loop and doesnt cover the whole range , but for a self modded cheapo induction kit the results are not bad
the results show that it is not running that far out as to cause damage ,

as you guys know any tiny leaks around the maf or what are deemed large maf tubes will stand out on l\v like a sore thumb so it can be used to determine if a maf setup is worth running with or needs tweaking
i,m not trying to be an arse guys , just showing my findings

Tony,

My bugeye (when bought) had a cheap and nasty induction kit fitted which altered the air flow past the maf, this made the maf send incorrect signals to the ecu resulting in the ecu thinking it was running lean to which it pulled timing and added 25% fuel correction (max allowed) iirc, so it was over fueling and running like a bag of shyte mate :thumb:

Off course increased air flow is going to cause changes to AFR's and boost Toneh

One car, one induction.

99% of the ones I see need remapping for it

Simon honestly mate I'm not disputing what you say at all , I just say what I find myself and my car ,, it just seems odd I never get all these problems everyone else gets ,

Tony

And Shaun

Without a doubt mate , but all my set ups have been within a range for the ecu to cope with

Tony

When you say "the ecu copes with" do you mean the ECU retards ignition through FLKC or FBKC?

And I've tried more than one set up mate before going mafless
And none what you would deem dangerous to the engine
I just don't get it

Tony

No mate i mean the set up I used never put it out of 5% Af correction range

Tony

L/v only shows a max correction of 14.99
And it's recommended don't go outside of + - 5%

I've had maf leaks that have not put it above 14.99 so Ive no idea what induction you were running to put it that far out because the one that came with my car was awfull , but I did mod it

Tony

No idea what kit it was tony, it was some sort of cheap alloy pipe with a naf filter on the end, when we plugged it in at G R Performance it was adding as much fuel as it could and was ticking over shyte, we fitted oe box ect and it was perfect (with the same maf). but on the other hand i have fitted induction kits on classics and some have been fine but some have not (piper didnt work)
varied results from all sides here mate :thumb:

Threads like this are good so we can all see each others findings :thumb:

Mmm does seem varied ,,, I must just be the luckiest scooby owner on the planet or good at guessing lol
Like I said at the beginning based on my experience and my car
Seems some of you guys do seem to get a lot of hassle when doing small mods
My induction was a crappy s shaped eBay job , and I cut it up and that learning view was the result ,

Tony