Help.. K&N vs Pipercross vs BMC

[GrahamS4]

I am really tempted, the science has sold it to me. The trouble is it's a case of once bitten twice shy regards oiled filters with me. What came 2nd?!

[Nige_RS4]

Does the BMC come pre-oiled?

[buzzard]

PMSL

(clue: it wasn't the f*cking paper one!)

p.s. sorry to come in late...

[Peakz]

When Doug's laptop died he also lost a fair bit of vital data, so the test results are now gone forever!

IIRC the standard paper filter fared quite well, it beat the (used and not so oily) K&N filter and the BMC panel filter was by far the best with the highest airflow reading.
The tests were conducted on the MRC test track with a virtually stock S4 (RS4 IC's, APR Bi-Pipe and MRC oil cooler), typically third gear wide open throttle (WOT) from around 1200 RPM to 7000 RPM.
The BMC certainly felt better especially since they were all compared directly with each other, we even retested the standard and K&N filters to be sure we weren't imagining the results.

[Nige_RS4]

Was the paper filter brand new, as clogged OEM filters are often used to show improved gains?

I'm not suggesting for a minute that MRC behave like this BTW!

[Peakz]

I'm pretty certain the paper filter was new, looking back at my service records I had the RS4 IC's and Bi-Pipe fitted in November which coincides with having an oil service and filters - the tests were done within a week or two of having this work done.

We only tested the used K&N because Doug had a spare one lying around, it wasn't dirty but it had very little oil left in it.

[GrahamS4]

Well. I have a local Edworthy's and their website quotes £34.99 for one of these. I guess all I have to loose is £34.99 and a new exhange MAF worst case!

Still feeling a bit chicken though to be honest!

A little concerned I would de-oil it sufficiently/correctly and also concerend that if they are designed to be oiled, do they sufficiently filter without the oil?

You go first Nige

[Peakz]

Graham stop being such a wuss and get a BMC filter, whilst you're at it get some IPA in a spray can to clean your MAF first, maybe even do a pre/post clean FATS run before you test the filters too.

[Nige_RS4]

You go first Nige

I think I'll hold off, my car is running schweeet at the moment!

[GrahamS4]

Graham stop being such a wuss and get a BMC filter, whilst you're at it get some IPA in a spray can to clean your MAF first, maybe even do a pre/post clean FATS run before you test the filters too.

If I do it I will do some before an after logging for sure. It was a kick up the backside that made me get the K&N on my last car. 20 miles later with a dead MAF I sure regretted it!

if they are designed to be oiled, do they sufficiently filter without the oil?

Probably what's holding me back most. Given the widley known issues with oiling and MAFs, surely if they didn't need to be oiled to some extent, they wouldn't be?

Lets not forget the filter does need to filter!


So are you running BMC Paz? Any deoiling like Julian or just straight in?

[Peakz]

BMC (red rubber surround) straight out of the box, they're not that oily perhaps due to using lighter/thinner oil?

[GrahamS4]

Cheers Paz. Well we'll just have to see, I might just get me one

[S4TAN]

BMC's are lightly oiled with a low viscosity oil.

As a further note for the interested: I've tried various filters in the past couple of years; K&N, Green, ITG, and now BMC - all of them pre-oiled ... not one has killed a MAF on my car ... EVER!

No bullshit - fact.

And getting a can of IPA spray is a great idea for cleaning MAF sensor elements if you're worried (it's a good thing to do anyway, even of you're running a non-oiled filter - blasts the fine particulate matter off the element and de-greases it - as said before: there is a fine engine oil mist in the intake system during normal operation, just take a look inside the entrance to the Y-pipe - you'll probably find a little pool of oil there - if this mist is present there then it's only a few inches away from the MAF sensor ... the oil mist will get blown across the sensor when your DV's open to dump boost back into the Y-pipe, and the sensor is designed to measure air in both directions ...)

[jimbogrey]

as said before: there is a fine engine oil mist in the intake system during normal operation, just take a look inside the entrance to the Y-pipe - you'll probably find a little pool of oil there - if this mist is present there then it's only a few inches away from the MAF sensor ... the oil mist will get blown across the sensor when your DV's open to dump boost back into the Y-pipe, and the sensor is designed to measure air in both directions ...)

Very good point

So do you think changing from an OEM paper filter to a BMC unit would increase airflow at mid range, peak flow or both, because if i could get better than 274 g/s on K03's that would be incredible and I'd buy one straight away.

Jimbo

[AdamS4]

So wheres the best place to get a BMC replacement panel airfilter ?