hi all,
i am not a motor mechanic, but i felt uncomfortable when i saw that ad before. my thoughts:
each design finally only uses as little of structure as possible. when jaguars engineers developed the air intake filter to the size of x and not x-d, then they had got a (or some) reason: purity of air-inflow, noise being generated by pressure pulses, interplay of intake and exhaust system, smoothness of ensemble.
i wouldn't change it just for the promise of some hp. if i wanted hps, i would go for chip-tuning (you call it ecu-upgrade).

p.s.: in my other car, a bmw z3, i like to hear as much as i can from the engine, and there bmw has even invented a device in the intake section to provide the passanger with sound. see here: http://www.unofficialbmw.com/images/...4%20Engine.pdf (page 10). do you want that effects in a jag?

regards, andreas

 

Hi! I have used K & N filters in all my vehicles for the past 10 years and will continue to use them in future ones. Primary reason: Helping the environment, since they are good for at least 100K miles if serviced properly periodically. This saves throwing paper filters away into the landfill every 20K or so. Cost is another factor. Add up the cost of papers (at least 5 @ $10 or more each depending whether from a dealer or discount store) and worse case is a breakeven. Have never had a problem with any engine using them. This includes a Porsche, 3 Corvettes, 4 Jeeps, Jaguars, and several Volvos. Quality of the product is good. Also, there is no change in air intake sound or noise level.

As far as performance claims go, I seriously doubt that there is much to them. I guess if your current air filter was dirty, replacing it with a new cotton based one would help mileage and maybe performance, but I've never measured either so I can't speak to it. However, I just got back from a drive to Northern California from So. Calif, 8K miles, and averaged 28 mpg driving at the 70 - 80mph limit. It also included 15% city driving. If this is common, then there is no advantage to using K & N. However, I feel better helping the environment, and that was important to me. By the way, I'm not an environmentalist or tree hugger, but some things make sense.

One final thought, Since the K & N filter does flow more air than paper, this might help your engine develop some horsepower at high RPM levels, where the paper one starts to choke up.

Good luck.

Niel

 

good arguments, i have to admit.
my impression was, that this just one of these products, that say: "throw out every piece of metal you don't understand, and what remains is good for more hps." (like they do it on motorbikes.) but as you describe it here, it is a good thing for the environment.
regards

 

Amen!!!