I have read that at high rpm's K&N filters actually allow the engine to lose power do to the fact that they suck in more engine heat then actual cold air. I have hold on buying one of them do to that fact. I leave in La and it gets pretty hot here sometimes in the triple digits. Does any one encounter this problem before?

 

Check with Porsche. Once again the gt3 rs 4.0 uses two k&n style intake filters.

 

The GT3 also has a huge scoop on the decklid to draw cold air into the engine compartment. I had the "Cold Air" intake on my car for a year and went through three MAF's and dealt with constant check engine lights. This was not an over oiling issue because MAF #2 was installed along with a dry cone filter from AEM. I'm guessing it's warmer air that shortens the MAF's life but who knows.

Loved the way it sounded but ultimately got rid of it because MAF's are expensive and check engine lights and rough running are a pain in the ***. Go ahead buy it and try it, you'll dig it for a while. Be sure to run the sock if you plan to drive through a carwash or put a towel over it if you're going to wash it without the sock on. Sock definitely kills some of the noise but is cheap insurance for water getting in the motor.

 

I have an '02 996. Several times with the car left out in heavy rainstorms the engine has run poorly to the point of stalling. Also noticed that it has run poorly after leaving spray car wash booth. I never had this problem on my '00 996 with the stock air filter so I suspect it is something to be aware off. I plan to start covering the filter at the car wash to see if it makes a difference.

 

I use a small towel when I wash it and try not to leave it out in rainstorms, but again the small towel would again do the trick I suspect.

 

The GT3 RS 4.0 has a scoop on the decklid AND two conical intakes. I had a conical intake (Jim Wolf Technologies) on my previous car for 9 years. Once I over oiled it causing my maf to get dirty. I cleaned the maf and never had a problem since (learned not to over oil).

I had the Evo CAI installed at the dealer along with the GIAC tune and never had an bad MAF to this day.

Aren't AEM filters for Honda's?
Pic below and here's the link to Motor Trend. http://www.motortrend.com/roadtests/.../photo_18.html

 

Ok so her is my hypothesis for the K&N filter upgrade. If its sound your after I think its the best do to the fact that is an open air box. If performance is what your after I don't recommend it.

And this is my opinion why. On the gt3 rs there is a carbon fiber casing that goes around the filter to protect it from the engine heat and unclean air that is produced by the engine at high temps. As we see in this picture there.
http://www.motortrend.com/roadtests/..._18.html#photo
In this picture you will see the rs has a scoop in the back to suck in clean out side air.
http://www.motortrend.com/roadtests/..._15.html#photo
The EVO CAI intake system also has a similar design with its plastic casing that shelters the air filter form the engine heat and unclean air. As we see in this pic.
http://www.google.com/imgres?imgurl=...QEwBg&dur=1189
Now guys correct me if I'm wrong. But is the fan that we have on our engine hood is meant to blow air out of the engine bay? That is meant to help cool that engine bay down a little. So how can we add in an unprotected air filter in an area where the air quality is not clean and cool?
In this pic the person actually removed the center fan to install the K&N system and it can suck in clean air from the outside.
http://www.google.com/imgres?hl=en&c...6&tx=109&ty=47

And yeah I know what you thinking. But Shaby the dyno test have proven that the K&N is a definite increase in performance. And your right, so lets look at how it creates that data. I have noticed that all dyno test are made in a carage with masive fans in the front and in the back with the engine bay wide open.
http://www.google.com/imgres?hl=en&c...:13,s:55,i:297
http://www.google.com/imgres?hl=en&c...:16,s:15,i:177
Which solves the hot and unclean air situation I'm talking about. So until K&N can produce a much better closed design to better protect the air quality then what they have on the market now, I'm going to wait or spend the money on the EVO CAI.

 

I got a '02 C2 as well with a K&N installed and today I had to drive through parts of storm Isaac for 3 hours straight from east florida to central. The filter held up quite well against it. Obviously I got the protective sock on it but i was really surprised cause that was some heavy rain fall.
I was running it steady at 2000-3500rpms in 6th and it was just fine!
Im probably gonna have to replace the MAF very soon...
as to the performance, I agree it losses sum