Descreening The Maff

[RobDon]

I've always felt my car runs better with the screen in place, tried both with and without. APR supply a screen in the stage 3+ kit, I doubt they'd supply a new part for no reason, seems a well thought out kit. Mine did 219g/s with the screen, 254g/s scaled.

 

[wayne lcr]

so is it a good or bad thing todo ?. i just got a new maf and dont want to butcher it then some thing go wrong or the maf packs in any 1 is it a yea or nay

 

[wild willy]

so is it a good or bad thing todo ?. i just got a new maf and dont want to butcher it then some thing go wrong or the maf packs in any 1 is it a yea or nay

My set up boosts better and pulls harder without it. Some people have removed the mesh and not seen a change in the maff readings at all, personally i think that the maff housing is not the biggest restriction in their set up.
If you have a spare housing give it a go and let us know your opinion and join in the debate.

 

[jamiebennett81]

My set up boosts better and pulls harder without it. Some people have removed the mesh and not seen a change in the maff readings at all, personally i think that the maff housing is not the biggest restriction in their set up.
If you have a spare housing give it a go and let us know your opinion and join in the debate.

new MAF arrived, but with the weather as it is, not safe to do any logging

once it has cleared up a bit I will post my results up

 

[wild willy]

new MAF arrived, but with the weather as it is, not safe to do any logging

once it has cleared up a bit I will post my results up

looking forward your results mate but don't risk yourself or the batmobile.

 

[ibizacupra]

No MAF.. best idea.. like my ibiza now.. well rid of the poxy thing. (and coil packs)
I might play with some logging when doing the manifold next step experiment on the Lupo

 

[jamiebennett81]

No MAF.. best idea.. like my ibiza now.. well rid of the poxy thing. (and coil packs)
I might play with some logging when doing the manifold next step experiment on the Lupo

OK, I am just gunna remove my MAF and coil packs, think it should work fine too as you have suggested Bill

 

[jonjay]

Only a back to back test on a RR would convince me. The screen is there to create laminar flow for the maf, not to keep crap out. You might get a higher reading (and therefore more fuel) without the screen, but it doesn't mean more air is flowing through the MAF.

Well having read this I am going to get spare maf housing and descreen it then do a before and after RR at AmD. I will report back with RR results.

I know its a deisel but heck principle is the same no?

 

[trebormint]

Well having read this I am going to get spare maf housing and descreen it then do a before and after RR at AmD. I will report back with RR results.

I know its a deisel but heck principle is the same no?

The smaller screen actually came loose from my maf (PD130) and caused an ECU fault!

Luckily found it loose in the silicone hosing on my CAI! Pushed it back in and the fault cleared straight away.


Fault was Mass Air Flow Sensor: Implausble Signal

 

[wayne lcr]

think i best wait till sum 1 does the logs and nos more about this ill keep a eye on the thead

 

[DPJ]

Seen the little thing in the end of your kitchen tap spout? That straightens the flow of water out. Ever tried taking one out? The water goes all over the place................

 

[jamiebennett81]

Seen the little thing in the end of your kitchen tap spout? That straightens the flow of water out. Ever tried taking one out? The water goes all over the place................

understand your point Dave, but moving a restriction is a good thing, but understandably can distort air and fuel readings...

 

[Feel]

Seen the little thing in the end of your kitchen tap spout? That straightens the flow of water out. Ever tried taking one out? The water goes all over the place................

Still ends up in the sink, though

 

[Robbie C]

Lmao

 

[DPJ]

Still ends up in the sink, though

Not if you move the spout over the worktop............

 

[TRUMPY]

I recently replaced my maff with a new unit and was pleased to reach 246g/sec, this was a little aggressive boost wise in the mid range so i made adjustments with my mbc and limited peak boost to produce 237 g/sec.
i have run a non screened oversized maff housing in the past that always produced good results but obviously under read. So i descreened a stock maff housing to see what the results would be.

Standard maff housing.
RPM Mass Flow Load
TIME
STAMP /min g/s %
150.96 2920 80.53 93.7
151.67 3280 138.47 100
152.27 3760 171.19 100
152.88 4200 186.39 100
153.48 4640 193.42 100
154.08 5080 210.69 100
154.69 5480 224.39 100
155.29 5840 231.19 100
155.89 6160 234.11 99.6
156.5 6440 235.94 99.6
157.11 6720 237.78 99.6

RPM Temperature Load Absolute Pres.
TIME
STAMP /min °C % mbar
150.66 2800 24 67.1 1330
151.37 3120 24 95.3 1790
151.97 3480 25 79.6 2490
152.57 4000 24 83.5 2540
153.18 4440 24 82.4 2530
153.78 4880 24 86.7 2510
154.38 5320 24 95.3 2400
154.99 5680 24 95.3 2350
155.59 6000 24 95.3 2300
156.19 6320 26 95.3 2310
156.8 6600 27 95.3 2220

Descreened Maff

RPM Mass Flow Load
153.4 3440 172.25 100
154 3920 190.11 100
154.71 4480 205.11 100
155.31 4920 216.36 100
155.91 5360 235.06 100
156.52 5720 241.53 100
157.12 6080 250.64 100
157.72 6360 253.36 100
158.33 6640 255.89 99.6

RPM Temperature Load Absolute Pres.
153.7 3680 24 5.1 2540
154.4 4240 23 5.1 2540
155.01 4720 23 5.1 2530
155.61 5120 24 5.1 2490
156.21 5520 24 5.1 2440
156.82 5880 24 5.1 2420
157.42 6240 26 5.1 2310
158.02 6520 27 5.1 2320
158.64 6720 27 0 2340

Descreened maff housing gives 255g/sec which is a nice gain. The cynical part of me says that since the meshing is there to straighten air flow into the maff, all i have done is messed with calibration. However when you see how much of a restriction the plastic and meshing is in the intake system it can be seen that air flow has simply increased. This is proved by the increase in turbo boost generated. More in = more out.
With further boost adjustments and an alteration to the intake system i'm looking for 270g/sec provided that the maff doesn't get maxed out.

hi willie, did you remove the mesh too?

 

[wild willy]

Removed it all mate.
Tell us how it performs on the butt dyno.

 

[M1KEH]

I think a dyno run with maf screen and without maf screen would be the best test of this. The improved g/s reading could just be that the sensor gets confused by the more turbulent air passing over it.

 

[ibizacupra]

or an actual dyno -

 

[TRUMPY]

Removed it all mate.
Tell us how it performs on the butt dyno.

did you get my pm mate?