Cold Air Intake and K&N Filters

[84porsche]

I have seen these two extra options added to VWs. I don't know very much about automobiles and what I know about Porsches I have learned from you guys. Can someone tell me what these will do and what if anything do they add to a VW.

[widebody911]

Depends on the VW - they wouldn't do jack for my 1960 panel

I have doubts about some of the cold air intakes I've seen, which consist of a long plastic tube leading to the fenderwell. My limited hydraulics knowlege sez there would be serious flow restriction in a tube that long.

I have a K&N on my 911. I just upgraded to a much larger version - this one has about 3x the surface area of the old one - and my gas mileage improved significantly; I think the original baby one was too restrictive.

Do a search thru the archives - lots of opinions on these.

[s_wilwerding]

An interesting side note:

On newer 911s with hot film Mass Aiflow Sensors, K&Ns have been known to cause problems. The oil in the K&N will get sucked into the MAF and cause it to fail. Probably doesn't affect the older 911s, but something to think about if you ever upgrade.

On the newer stuff, the majority opinion is to stick with stock air filters.