Cone filter, was Stone Gray '91 200q at Waterfest

Brandon Hull Hull at
Tue Aug 13 14:36:33 EDT 2002

the website used to have a link to a complete post from Ned Ritchie on this topic.  The essence of the post was that one of Ned's customers was having a mysterious miss in his mega HP urS6 at higher rpms.  After trying everything else, someone removed the cone filter and re-installed the stock box, and the miss went away.  Ned's hypothesis was that the shape of the swirl of the air coming through the cone was messing up the MAF sensor.  I'm guessing there were confusing high and low air densities running across the MAF wire, and it sent some error message which either cut boost, retarded spark or whatever.  Again this was a high HP (350-400) high boost application.  But my car, and every other eS2 I know of, has stuck with the RS2 airbox rather than aftermarket.

I suspect Ned's post is still in the archives, although it was long enough ago that I'd check the quattro list archives rather than 200 or s list.


> >I don't see anything wrong with having a cone air intake. It
> might not have
> >great benefits running it without a heat shield but it won't
> have any negative
> >effects either. Plus the sound is too cool to keep it locked
> up inside a box.

> somewhere in the s-car list archives (and possibly also on
> the 200q20v),
> from a ways back when, and from a notable authority in
> boosted 20v engines,
> you'll find reference to a cone filter not smoothing the flow of air
> properly for the MAF sensor.

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