Are the RS2 and S2 MAFs the same?

[crameradam]

I don't think they are, but I'm not 100% sure. I'm looking to purchase an RS2 MAF (034 133 471 N). I found a good deal on an S2 MAF, but I want to make sure it's the same part as the RS2 MAF.

The seller said they are the same.

Thanks,

Adam
95 S6 Avant

[rotoryboy]

They are except the RS2 one has no mesh.

[crameradam]

They are except the RS2 one has no mesh.

No mesh? Are you sure about that? I thought all Audi MAFs came with some sort of screening.

[rotoryboy]

or less mesh
rs2 on right

[blu_s2]

RS2 MAF has a plastic (not metal) mesh with larger 'holes'

[crameradam]

Thanks. So, when you guys upgrade to RS2 specs, do you normally just remove the screens or buy the RS2 MAF?

[RomaS2]

We just leave S2 maf, no need to replace it really.

[Billman]

Or just take the densy net from the S2 maf and leave it without one or make some more free flowing!

[crameradam]

Or just take the densy net from the S2 maf and leave it without one or make some more free flowing!

So, is there any advantage at all to buying an RS2 maf?

It sounds like I should just take the screens out of my current maf (I have the AAN engine, not 3B or ABY)

[Kodiak]

I'd like to know more about this, too. What effect on airflow do those screens really have, and what role, if any, do they play in protecting the engine from nasty bits of stuff?

[Lee]

Screen stabilise the airflow theoretically. This ensures that the airflow is calibrated over a larger range as it sets up the required air turbulence. RS2 screens are larger, maybe to present less restriction, but its function is still the same. It doesn't protect your engine from crap...that's the job of your upstream airfilter.

[Kodiak]

Screen stabilise the airflow theoretically. This ensures that the airflow is calibrated over a larger range as it sets up the required air turbulence. RS2 screens are larger, maybe to present less restriction, but its function is still the same.

So there's no benefit to removing the screens, then? Or to running an RS2 MAF without commensurate engine mods?

[S2central.net]

The *alleged* benefit of the RS2 screens is they provide less restriction than the ordinary S2 MAF screens.

I haven't found anywhere that can flowbench the MAF - in order to characterise the Vout signal - with and without screens. I'm going to see if anyone in the local Aero trade have access to a flowbench thats up for ~450lbs/min.

I haven't yet tried to VAG-COM data log any before or after readings.


Paul

[horvathg]

I've changed my MAF from S2 to RS2 a week ago and nothing has changed, at least nothing obvious. I'll take it for a longer ride today to see consumption. My calculation would suggest that the S2 mesh gives a surface area of some 5-6% of the inlet diameter (and on the other side too). It may not count on low rpms I think. Higher rpms we never use

[crameradam]

Thanks for all of the input.


In the end, I decided to shell out the cash ($270 US) and get the RS2 MAF (versus keeping my S6 MAF and removing the screens). Since I've already spent so much $$ on the RS2 conversion, an extra couple hundred is worth it to make sure the car runs properly.