MK5 Golf GTI
All Things Mk5 => Mk5 General Area => Topic started by: Shorty on January 29, 2013, 07:43:24 am
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As above, does anyone know off the top of their head the size of the MAF housing used on an ITG?
Is it 3"? I'd measure on my car but can't get to it at the mo.
Just trying to work something out, if it is 3" then that's quite a bit larger than the standard airbox size MAF housing, meaning the MAF would be out and not read correctly..
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it is a stock size MAF housing on the ITG. The only non stock maf intake I know of is the VF Engineering one. :smiley:
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Its 2.75 inch iirc.
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If its 2.75" then that's 25% bigger than standard, so quite a difference!
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I also think the itg maf housing has approximately the same cross-sectional area as the stock one. If you look at the fuel trim values for alot of folk on here, they are usually close to zero.
Are you having an issue seeing that you had recently bought a new maf?
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I also think the itg maf housing has approximately the same cross-sectional area as the stock one. If you look at the fuel trim values for alot of folk on here, they are usually close to zero.
Are you having an issue seeing that you had recently bought a new maf?
At what state of tune are the trims ok? Would it not be fairly ok on standard but then at more boost, say stage 2+ the trims would be higher because of more air? My friend is custom mapping my car and at high boost it's backing everything off because its running out of fuel.
We originally thought it was the MAF but the same with a new MAF, hence why I am selling the new one.
If you look the standard airbox housing is an oval shape which is 3" x 2" and if the ITG is 2.75" then that works out at 25% bigger which is the difference we are seeing, so would make sense.
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Has you logged your lpfp rail pressure as being able to supply the required fuel?
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Yeah rail pressure is fine...
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Yeah rail pressure is fine...
But was the LPFP actually logged?
The higher tuned cars can stress the LPFP and cause it to starve the fuel rail of fuel if it's output is sub-optimal.
Also are you using an uprated hpfp and is your cam follower in good condition?
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Yeah I have Autotech internals and the follower has done around 3,000 miles. Rail pressure is deffo there it's just the air side of things. It's fine at 1.5 it's just we want to run more..
Going to have a look at re calibrating the MAF and going from there.
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If its 2.75" then that's 25% bigger than standard, so quite a difference!
I thought the MAF housing had to be the same as OEM? Otherwise running into scaling issues
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If its 2.75" then that's 25% bigger than standard, so quite a difference!
I thought the MAF housing had to be the same as OEM? Otherwise running into scaling issues
Yes you are right Rich. Up to a certain point the ECU can adapt using the fuel trims, but once you get past that point it needs to be MAF scaled. GIAC extreme maps use MAF scaling and it is why I'm changing my intake from Evoms to VF.
:smiley:
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If its 2.75" then that's 25% bigger than standard, so quite a difference!
I thought the MAF housing had to be the same as OEM? Otherwise running into scaling issues
Yes you are right Rich. Up to a certain point the ECU can adapt using the fuel trims, but once you get past that point it needs to be MAF scaled. GIAC extreme maps use MAF scaling and it is why I'm changing my intake from Evoms to VF.
:smiley:
This sounds about right, the ECU can adjust it but only upto a certain amount of boost by the looks of it.
By the looks of it most normal stage 2+ set ups can deal with it, it's when you go that little bit further that it becomes a problem...
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Sounds like the low pressure fuel pump inside the tank cant cope. Log block 231 and see if its dropping below 4 bar. If so then give me a call for an uprated pump. The itg wont be the issue. Run that kit with 1.9 bar peak and 1.7 hold with no issues.
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Alex what sort of money are we talking about for an uprated lpfp?
Is block 103 measuring the same parameters as block 231 for low-side feed pressure from the tank?
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£275 inc vat for a drop in replacement pump.
231 shows requested vs actual and pump load.