Descreening The Maff

wild willy

Full Member
Aug 4, 2003
2,323
0
Wales
Trust your air filter, and service it regularly (to check it) and it'll be fine.

I did mine (stage 1 LCR) and don't recall that much difference - but mine never had high g/sec figs like some others.

With a free flowing filter, it's entirely possible that a screened MAF becomes the next restriction. Not sure that a descreened MAF would be beneficial with a less free flowing induction system, and let's not foget that your setup can obviously pull more air - so it is restricted by a screened MAF (a St1 or St2 with OE turbo might not be able to flow more).

Good results though, you must be pretty happy with your setup, now ::thumbup:
I am happy with the set up at the moment, but the cars days of reckoning is soon with a RR session booked for the end of the month.
I'm really tempted to refit my stock k04 to see what i can achieve with it.
 
Nov 2, 2004
9,335
0
South Wales
Such a shame that i wont be at the RR day to see how it runs. Sounds like an interesting mod tho, i might try this on mine as i have a 12" pipe straight to my MAF so the flow is pretty straight by the time it hits it i reckon.
 
Jun 17, 2007
1,032
0
Aberdeenshire
Would this be worth doing to my LCR Maf with an ibiza element in to suit ko3 hybrid applications?

Can this damage the elemt at all? Will it be of any great benefit even though every little helps!
 

jamiebennett81

Guest
I would just like to say, that this is far from easy, and as said, this is a right PITA to do

the mest would not leaver out at all (if I applied anymore pressure then I was in risk of actually damaging the MAF housing) and in the end I had to get the dremel and cut the plastic mesh to bits and snap it out of the MAF shell (gently of course)

I was reading around 202g/s last time, and even with a failing MAF element (which a new one is arriving from Bill tomorrow) I should see some increases hopefully

I am just about to go and reinstall it and then get VAG COM on it

I will be back with some logs.....
 

jamiebennett81

Guest
ok, so some logs have been done

now the synic in me tells me that because its colder, the MAF is reading higher, but I dont know if temperature can effect a MAF, or certainly effect it that much from the increase in g/s on the logs

here is a log I did a couple of months ago, highest reading was 203g/s

(ignore the boost in the following logs posted, as its all over the place due to boost leaks which I am currently fixing)

Before descreening the MAF

Code:
0.8	2080	103	8.16	44.08	1.22	2160	111.3	2460	1510
1.61	2240	120.3	9.52	54.47	2.01	2320	131.6	2490	1770
2.41	2400	143.6	11.22	71.83	2.81	2520	153.4	2510	2170
3.21	2640	160.9	13.6	86.67	3.63	2760	159.4	2530	2410
4.03	2880	159.4	14.96	87.06	4.53	3080	163.2	2520	2420
4.93	3200	162.4	15.98	99.64	5.33	3320	165.4	2440	2410
5.74	3480	169.2	16.66	112	6.24	3640	172.9	2390	2420
6.64	3800	175.2	17	127.17	7.15	3960	174.4	2440	2450
7.55	4080	176.7	17.34	139.92	7.95	4240	178.2	2420	2440
8.35	4360	178.9	17.68	146.19	8.75	4480	184.2	2380	2470
9.15	4640	187.2	18.36	164.64	9.55	4760	178.9	2340	2410
9.97	4880	180.5	17.68	165.47	10.37	5000	178.2	2320	2360
10.77	5120	176.7	17.68	173.58	11.17	5240	177.4	2320	2370
11.57	5360	176.7	18.02	181.22	11.97	5480	178.2	2320	2310
12.37	5560	175.9	18.02	187.92	12.78	5680	173.7	2320	2360
13.28	5800	169.9	17	190.36	13.68	5920	169.2	2330	2330
14.08	6040	169.2	17	194.11	14.49	6080	167.7	2350	2310
14.99	6200	165.4	16.66	196.64	15.39	6280	164.7	2370	2330
15.81	6360	166.9	17	197.61	16.3	6440	163.2	2410	2290
16.7	6480	162.4	16.66	200.72	17.12	6520	162.4	2420	2270
17.52	6600	160.9	16.32	198.72	17.92	6640	157.9	2430	2260
18.41	6680	158.6	15.98	202.75	18.81	6720	156.4	2430	2270
19.23	6800	155.6	15.64	203.06	19.63	6840	154.9	1370	2280


After descreening the MAF

Code:
60.15	2000	34.6	1000	1050	60.55	2040	42.9	4.08	21.83
60.95	2080	85.7	2480	1090	61.35	2160	99.2	7.48	44.22
61.77	2240	112	2450	1360	62.17	2320	124.1	9.18	57.92
62.66	2440	141.4	2470	1810	63.18	2560	163.9	12.58	84.5
63.58	2680	176.7	2500	2380	63.98	2840	169.2	14.62	88.36
64.38	3000	173.7	2540	2420	64.78	3160	172.2	14.96	104.25
65.18	3320	175.2	2430	2420	65.59	3440	182.7	16.66	123.08
65.99	3640	186.5	2380	2420	66.39	3760	185	17	134.19
66.79	3920	184.2	2410	2450	67.19	4080	188	17.68	145
67.59	4240	191.7	2380	2430	67.99	4400	191.7	18.02	159.39
68.39	4560	188	2340	2440	68.81	4720	188.7	17.68	169.67
69.3	4880	186.5	2300	2400	69.7	5000	188	18.36	178.67
70.22	5200	185	2290	2350	70.71	5360	185.7	18.36	190.58
71.11	5480	185	2290	2320	71.51	5600	182	18.02	192.53
71.93	5720	181.2	2290	2350	72.33	5840	178.2	17.68	199.53
72.73	5960	176.7	2290	2320	73.14	6040	174.4	17.34	200.81
73.64	6160	173.7	2320	2310	74.04	6240	169.9	16.66	200.5
74.44	6320	168.4	2350	2350	74.84	6400	166.9	16.66	203.94
75.24	6480	163.2	2380	2330	75.64	6520	164.7	16.32	204.39
76.05	6600	163.2	2390	2290	76.45	6640	164.7	16.32	206.86
76.85	6720	160.9	2390	2300	77.25	6760	158.6	15.64	206.06
77.67	6800	160.2	2390	2290	78.17	6880	159.4	15.98	202.75
78.57	6920	159.4	2400	2270	78.97	6960	155.6	15.3	210.67
79.37	7000	157.9	2400	2260	79.78	7040	152.6	14.96	209.83

as you can see, the MAF is now reading 210g/s as its highest reading

a healthy gain of 7g/s on just descreeing the MAF

now bear in mind, my MAF is a pretty "tired" so I expect some conserable gains to be had once the new MAF arrives

next up is fitting the new MAF (hopefully tomorrow night) and some fresh logs to be done

also my LCR airbox has arrived so I am going to look into fitting that to see if any further can be had :)
 

wild willy

Full Member
Aug 4, 2003
2,323
0
Wales
Only just picked up your pm mate, sounds like its all sorted.:)
With a new maff and this mod i think you'll see a little bit more than 202g/sec.;)
 

jamiebennett81

Guest
Only just picked up your pm mate, sounds like its all sorted.:)
With a new maff and this mod i think you'll see a little bit more than 202g/sec.;)

yeah no worries chief, thought I would try and crack on with it

perhaps you were lucky with being able to pull it out. I did drill the ten pence size hole as you first suggested, but it wouldn't budge, so out came the dremel:D

either way it did the job

perhaps its just cold, but it does feel like its pulling well at the moment, despite its surrounding issues

and thats 210g/s now....... ;)
 

jamiebennett81

Guest
Your boosting really well mate. I'm expecting 220g/sec from you tomorrow night.

yes the clamp on the DV was knackered and would not tighten properly, so I replaced that tonight

I see you mentioned that you turned down the boost after this modification? as and when I receive my new MAF and its fitted, is it wise to watch my boost, as in, will it be wanting to boost more due to the higher g/s?
 

wild willy

Full Member
Aug 4, 2003
2,323
0
Wales
yes the clamp on the DV was knackered and would not tighten properly, so I replaced that tonight

I see you mentioned that you turned down the boost after this modification? as and when I receive my new MAF and its fitted, is it wise to watch my boost, as in, will it be wanting to boost more due to the higher g/s?

You've got nothing to worry about mate since you have a custom map (a good one at that). I'm running a hybrid on a standard stage 2 map with modified boost request from Vtune, for me to request more at the red line the boost request for the entire rev range is increased. I therefore excercise a bit of restraint and turn things down a little.
Other than poor breathing (restrictive TIP and air filter) it has to be the maff thats letting you down a little. Your day of reconning is tommorow night.:)
 

jamiebennett81

Guest
This is something i need to try out, got a spare maf housing here i might butcher.

I think its worth it Phil

be interesting to see what you make of it and what your logs show
 

DPJ

...........
Dec 13, 2004
7,996
2
NN Yorks / Salento
www.seatcupra.net
Of course the MAF measures airflow through a diddy little hole in its sensor. The software scales it to give you the g/s flowing through the tube. If the screen does indeed give laminar airflow to ensure an accurate reading at the sensor, removing the screen could be giving a skewed flow through the diddy little hole. That would give a false flow reading, affecting accurate fueling.............
 

jamiebennett81

Guest
Of course the MAF measures airflow through a diddy little hole in its sensor. The software scales it to give you the g/s flowing through the tube. If the screen does indeed give laminar airflow to ensure an accurate reading at the sensor, removing the screen could be giving a skewed flow through the diddy little hole. That would give a false flow reading, affecting accurate fueling.............

Sorry unsure of your opinion Dave - not agreeing its worth it then?:(

so next step is to log fueling for my next set of logs to ensure its spot on?
 

DPJ

...........
Dec 13, 2004
7,996
2
NN Yorks / Salento
www.seatcupra.net
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.
 
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