We're talking strictly of the air filter element itself, not modifications to the air inlet system.

 

Most OEMs do not manufacture their own filters, spark plugs, wiring harnesses, switches etc. but buy them from outside suppliers. If there was truly something to gain Jaguar, or any other OEM would install genuine K&N filters at the factory and resell them as factory spares.

 

It's like Ground Hog Day ...

 

Thanks OP for opening the Pandoras Box on this topic..lolzz

 

+1

Depending on other mods that increase airflow, the K&N filter experience I have is pretty positive. I could cleary see a vacuum de-crease in the intake, even when the K&N filter was already pretty dirty compared to a new paper filter. And vacuum on the intake/boost on the outlet of the SC will determine the power consumption of the SC itself.

It is very expensive to test out the filter on a dyno (especially with our water to air intercoolers) as it takes a lot of time, my best guess would be between 5 to 10 hp (on a str), and that would just fall between the error margin of doing a dyno. Cheapest mod there is in cost/hp, so a good start imho.

As long as everyone posts true experiences instead of second hand stories/opinions this thread could be very informative, braking the ground hog day...

 

I think that's a fair point and I have noticed a bit more noise on my Suburban between the the two but not that much as it's already a noisey vehicle. Now the Jag is supposed to be a refined quiet vehicle 'cept for that supercharger whine ... so maybe it would help some.

 

Yup.... Kind of like the whole wheel / tire thing... Darn it people, if someone wants to put 19" rims or K&N filters on their cars, give them help, like what offset is good or "don't over oil". My Jeep Cherokee's with the 4.0 loved the K&N. My Honda's with the 17's and 18's were cornering beasts for generic front drive coupes. Heck, I even installed the AEM intake while the Accord was under warranty since the dealer sold them as accessories!
The point of my rant is really these things are a personal choice and if used properly (correct oiling, correct offset, etc.) they will not hurt the car. I see us being here to help people not impose personal judgment. Now if someone comes on here wanting to install huge negative offset wheels I'll be sure to tell them what suspension damage they can cause by doing it. Also, if someone wants to stick "Home Depot" weather strip on their car I'll speak up as well.
Sorry for the rant, but at times these "judgmental" threads just become counter productive...

Now I don my flame proof suit...

 

I guess you'd almost have to do the test after a complete cool down and timed warm-up cycle under identical conditions between each run. If you have a research lab maybe ...

I think you'll get at least that kind of variation just between launches in mild or hot weather. I think it's going to be hard to feel 5-10 HP on a car like the STR with so many things that can affect it's power output.

Bob S.

We can start this thread again in February when the Groundhogs get checked.

 

See you then ;-)

 

That's it. I am going to run without a filter......

 

Actually not a good idea, however it will improve the airflow as I have measured again a drop in vacuum (above that of the K&N). What didn't work nice was the altered airflow pasing the MAF, this caused the MAF readings to become erratic, and thus also unpredictable A/F mixture as the ECU is using the MAF as its base signal for fueling under WOT. A filter actually helps a bit to smoothen the airflow over the MAF (due to the sharp bends the air has to take).

Sorry ;-)

 

Heh, I was only joking

 

Of course you where ;-)

 

Agree. I have the K&N FIPK on my ZJ (Grand Cherokee)4.0. In conjunction with a Borla header kit and stainless exhaust, there is a noticeable bump in grunt over the stock set up. The ZJ intake was not an engineering marvel, bends, twists, small airbox that was relatively well sealed to prevent water from getting in when fording. This is not a premium vehicle, it's designed for mass production at low costs and high profit margin.The real difference could be felt was when i towed things, much less gear hunting, quicker throttle response.

Oh, and it's loud as h*ll.

The BSR open intake I have on my SAAB turbo seems to have helped a bit with turbo lag. And it makes a cool noise too.

I believe there is a great amount of variability of the effectiveness of a K&N filter or similar depending on the general properties of the vehicle itself, other modifcations made (exhaust, chip, etc.) to make a blanket statement saying "it works" or it "doesn't work."

That's my $.02 anyway, groundhogs be damned.

 

You should have felt the improvement on my 2001 Durango R/T when I put the K & N FIPK. Was a huge difference.

I watch a lot of car tv on the weekends and I have seen Muscle Car do dyno tests on a variety of cars, before and after, a CAI or K & N intake swap. Everytime there were gains in the 5 - 10 HP range.

 

I agree with your analogies- but the specific request was a recommendation for an air filter that gives increased performance. That's very different than asking 'will a K&N hurt my engine and help me pick up the babes'.

Without replaying Groundhog, there is no hard evidence to support the K&N filter (on it's own) providing increased performance.