So I bought a K&N filter and put it in and I was convinced I was losing power so i put the stock filter back in (this was a few months ago). I just recently decided to reset the ecu and start fresh with the K&N in and really romp on the gas. Still wasnt impressed with the turn out...put the old filter in and took her for a spin again. The difference is so subtle im thinkin the K&N was a waste of money plus the stock filter looks like it would filter MUCH better.

Does anyone have the raw data of a 4th gen dyno with the K&N vs the stock filter?

Anyone have any other input?

I have put K&N filters in all my and my wifes cars. I don't know if it actually does anything. But it is nice to not have to clean/ change the filter for a LONG time.

I've heard some horror stories of K-N filters causing problems with EFI systems. Something about the oil from the filter getting on sensors or airflow meters and causing issues.

That being said, I bought one and put it on my bike. It definitely increased airflow as I couldn't use it as the stock jets were no longer enough (its got 4 carbs).

Personally, I think they're a waste of money for an otherwise stock vehicle.

The K&N gives a little more sound/tone at WOT with no gains. It is worth using because it should last the life of the vehicle and only needs to be cleaned every 25K miles. The problems some people are having with the K&N is that they over oil them after cleaning. The trick is to dampen them with a paper towel to get the excess oil off before re-installing them. UOAs have shown that the K&N does as good a job as the OEM as far as filtering so there are no worries about efficiency. I

I use the TRD too, it seems to have more surface area.

After i put mine in a few weeks ago, the computer said i have 430 miles on a full tank of gas where as before it said 405...

I have never seen a tank say anything more than 360. What engine do you have 6 or 8?

oh6SR5 has a V6. It says it in his signature.

When I bought my 4runner it had 18 miles on it, I took it off the lot went straight to the auto store, bought a K&N filter and installed it in the parking lot, (yes occasionally I am that guy that does auto work out in front of the auto store) I just recharged/cleaned mine with 25k, I also did it at 12k as well. I check it with every change of the season to make sure it is not super dirty. I never noticed a difference in performance because I took the OEM filter out as soon as I bought the 4runner. I over oiled the filter once and had no issues. It driped down into the bottom of the air box and out the little holes, down into the passenger side wheel well and on to the ground. I think it is a good investment because you do not have to buy a new filter every time, just clean the one you have with the recharge kit.

I fill mine up everytime and it has never said under 400...

Sure does... Dee De Dee!

I wonder if there is a difference between the fuel capacity on the 06 vs the 04 4Runner.

flat pannel K&N filters are worthless....3hp max in most applications.

MAF issues are abundant with K&N use because of user error...

Usually if you flow more air in , you have to flow it out. hence why people do intake and exhaust mods.

The both are a waste of money with HP gains. You get extremely small gains for the amount of $$$. I just talked to a guy who put a Bassani exhaust on and said they claimed 50 add'l 50 HP.

I have a K&N FIPK system on my Cobra. It does really help a lot. I also have a blower/supercharger on the car so the induction is forced in through and out the exhaust ( Magnaflow)

On a stock vehicle an after market exhaust and a K&N are a waste of money. They can actually rob you of torque , any HP gains ( if any ) would be at wide open throttle. I've seen enough experiments on the dyno jet with this many times.

If you want a better air filter I would suggest looking at a TRD .

KOZ, what have you noticed with your TRD filter ? any better milage ? any better throttle response ?
How is the price compared with the K&N ? Input on the TRD filter would be appreciated.

I don't think you will see any gains from any drop-in filter. I feel that a better flowing air filter compliments a better flowing exhaust and the combination may give a slight more gain then just an exhaust alone.

The TRD filter seems to be made with better materials and they fit better.

TRD filter is made by http://afefilters.com/

Since TRD is a Toyota company I felt that if there were any warranty issues, I would be better off with TRD.

I don't think there is any performance difference between the K&N and the TRD, drop-in.

Koz

Turbo cars are really the only ones that benefit from almost no backpressure and any mod to let more air in and let more out will see a gain.

I hacked my aircan and fitted it with a modded K&N drop in filter and saw about 11hp on an AWD dyno with my '93 Eclipse GSX and with an exhaust I dropped just over a half second in my 1/4 mile time and even a little more by replacing the cat with a test pipe.

Depending on the way an engine is designed and tuned from the factory, adding an intake and exhaust can make really good gains and can also give very little. You should see some! There are other benefits like an air filter that lasts the life of the vehicle and that warm and fuzzy feeling you get when you hear that nice aggressive purr the engine makes.

Koz