MAF's

[Rob W]

Just cleaned left my MAF soaking in some Isopropyl,it only has one screen on the inlet side.What is the difference between an S2 & RS2 MAF?

[Greg_S]

RS2 MAF has a plastic latice that has bigger holes.

the S2 maf has metal close nit wire mesh on both ends.

Greg

[Rob W]

Hi Greg cant just the lattice be changed then,obviously it inreases airflow,is there any reason not to replace it with another lattice with slightly bigger gaps?

[Beetie]

Noticed on mine that it is missing the mesh aswell. I was hoping that i could find a mesh to put on.
When i start my mods, is it best, with the RS2 turbo, etc, to use an RS2 MAF aswell, or is it not critical?

[SteveH]

Guys,

I'm getting a carbon fibre MAF body next week. It's 10% wider than the standard S2 MAF and should help top end flow. The guy who makes them has done lots of tests and found this is the limit with the standard internals. Any larger than this and you experience problems at idle, due to low air pressure in the MAF body. I'll take some pics of it and let you know how well it's made etc. It will require changes to the ECU mapping and as a result it's not just a straight swap to use it I'll have a chat with Mihnea about it and see whether it's a worthwhile upgrade for higher flowing motors.

[Rob W]

As far as i can tell both MAF's are the same other than different screen/s,so the RS2 one is less restrictive to airflow than the S2,but is more likely to suck crap into the engine.
Oh and mine runs smoother since cleaning the MAF,dont know about fuel consumption yet.

[Lee]

They are probably calibrated for a different range of airflows. Higher flowrates are likely to require a higher current through the wire in some very high flow applications. I altered a resistor when I fitted the RS2 ECU to make it compatible with my ABY MAF. Screens are there to stabilise the airflow not catch crap...your filter should be doing that! The screens are part of the MAF system and removing screens probably change its caracteristics or consitency. MAFs are more than just the hotwire but a bit more than that as they manage the airflow locally around the wire too.

[Rob W]

Thanks for clearing that one up Lee,i was wondering why anyone would pay ££££ to change to nearly the same part,but in essence,they are different

[Rob W]

So how would adding an RS2 turbo into the equation,affect a standard MAF,would the flow still fall within its parameters?
Im just trying to find out how important it would be to change the MAF.

[Lee]

Mihnea's your man for that question. All I know is that if the screens weren't there for functionality then Audi would not have gone to the expense of fitting them. Car manufacturing is a business and the manufacturers get away with as little as possible to get the job done. Everything is engineered to minimal cost for maximised profits..

[Beetie]

I just said turbo as a starting point for the mods. Hopefully ill get the EM, intercooler, injectors etc and a remap from mihnea, and one of pauls chips, but wondered whether the standard MAF would alter readings to the ecu....

[audiman]

Im using my std S2 MAF on my setup with no probs. MAF limit is altered during the mapping period. As some ppl have said the most 'obvious' difference between RS2 and S2 is the screens. Mine is missing a screen. Probably got dragged through a turbo at some point in the cars life Before i got my hands on it.

[Beetie]

I knew it wouldnt really drag s*!£ through it but wondered on its limitations as such. Now i know yours tom is being used with a decent setup whilst standard, its something less i have to change! Although itll probably want cleaning a bit!

[audiman]

Due to the excessive wear in the bores and the engine breathing heavily it is caking the MAF with oil mist all the time. The thing still works fine but i do clean it every now and then. But it gets ****ty again within 2 weeks. So i have sort of not bothered for a while

[Rob W]

What mileage you on Tom?