I have to do the A12 service. Has anyone used the K&N replacement filter? Any insight on it or thoughts on it?

 

its not going to provide any MPG or performance gains.

 

I had an old 04 V6 Accord, and my gas mileage got worse with the K&N filter in it. I was getting about 25-26 MPG on my 9 miles commute to work. I put in a stock paper filter, and it jumped to 29-30 MPG.

Leave it out of your car.

 

On the plus side, the K&N lets more dust into your motor........uh wait....

 

Stock is better, in every way. I even took out my K&N typhoon intake to put back in the stock air intake and the original filter. Better filtration and better low end torque.

 

Are you guys talking about this filter?
http://www.knfilters.com/search/prod...x?Prod=33-2379

 

^why, yes we are.

 

yes. Or any K&N gauze type filter for that matter. They allow more in by filtering less. A net loss for your engine in the long run. The stock 2-stage paper filter is not a restriction.

 

roger,

I'm clueless about this stuff so i read as much as i can then ask dumb questions :p

So this one has oil in it correct? i wanna avoid that anyways.

So you guys swear by stock filters? no other performace filters?

 

^We don't use a MAF sensor so the oil isn't as big of a concern. The filter or box is not the limiting factor in the intake of air. So staying stock is fine.

 

Yeah. You can use an aftermarket pipe-style intake to tune the pressure wave harmonics from the intake valves opening & closing. This can actually gain torque/power in a specific rpm range if designed & tested correctly. This is how aftermarket intakes work. Nothing really comes from the performance air filter on the end. Usually the cold-air style intakes are the mst popular because they add more torque to the mid rpm range where people use it & feel it the most. Short-ram intakes typically boost torque in the upper rpm range where you spend very little time. This causes people to not feel much difference in everyday driving, but they are great for racing. The OEM intake is very long and snakes every which way. This boosts low-end torque. Also all the extra boxes and off-chutes help silence the valve noise which helps sell cars to average consumers.

But as far as drop-in filters go, OEM is the best.

 

Are there any other reusable ones out there? Paying 50 bucks once is better than spending 40 every few months till you get rid of the car.

 

40 bucks every few months!?
you're throwing a perfectly good air filter away.

 

OEM filter is $20. Replace it every few YEARS!

 

Well damn. I bought this filter a few weeks ago.

 

I have the K & N drop in. I didn't notice any change in MPG, sound, or performance. I wasn't expecting to just hope that it is better, lol. Truth be told, I just wanted another sticker for my toolbox.

 

Wow... Really glad I found this Thread. Was just about to get a K&n filter and saw this. Guess I won't be doing that anymore. Thanks for knowledgable advise guys! I'm learning as I go...

 

I hate to say it but restricting the intake side will never do anything but reduce power and torque. The throttle body is the purpose made restriction in the system. Until you have something with more restriction than the TB, the TB will always determine hp and torque. At full throttle I could measure no vacuum before the TB even with the OEM filter in place.

Any intake tract tuning is done after the TB; heads and runners. There's just no scavenging/ram air/harmonics effect to be had before the TB. There are certain very highly tuned applications where this is possible but the effects are only there at or near full throttle and it's usually with multi-million dollar budget race teams, not your typical aftermarket pipe with an air filter at the end. The further you get from the intake valves the less it matters. There should be no real harmonics before the plenum as the open space lessens or eliminates them.

The pre-TB side is as simple as making sure there's no restriction with good quality air and you're done and the stock setup does a good job with that.

I fully agree with the rest though.

To the OP, I live in a dusty area and change the filter every 40,000 miles or more. No need to ever change every few months. MPG can't change from a dirty filter, the only that will suffer is power and that would only be with an extremely dirty filter and only at or near full throttle.

 

If that was the case, wouldn't a velocity stack right on the TB net the best results?

Every all-motor Honda I've seen features a custom length Intake pipe. In fact for a while, the plenum + intake cars were making more power than ITB cars. I think that still may be the case. I know Endyn doesn't use ITBs on their race motors.

 

After the tb? The problem with everything besides wide open throttle is the tb is impeding airflow making any ram air effect useless in two ways. If the throttle is partially closed, the driver doesn't need full throttle and two, with that huge restriction in the middle of the airflow it kills"tuning". As I mentioned, it can be done. But its going to be in highly optimized race setups, not a tl with a pipe and filter with no r&d, with fitment being the biggest priority.

I don't doubt the plenum cars make more power, the plenum can be somewhat tuned and coupled with runner tuning you can get a flatter torque curve with the same peak power.

The big issue I was getting was that you can't increase low end by creating a restriction. While there are cases this can be done on the exhaust side, restricting the intake will never result on a gain of any kind. If that were possible you would make more torque at part throttle when the throttle body is restricting flow.

 

 

Lol. It makes my head hurt... especially this morning. I appreciate your feedback and opinions on this subject as you're more heavily involved in the Honda tuning. I've been on the sidelines for the past couple of years.

 

I'm always up for learning new things. Especially first hand experience.

 

ummmmm i was about to go buy a k&n filter but i guess not now, i get 18 mpg with the stock filter, if i got the K&n filter i know i would of dropped even more..thanks guyss.... am new with this car..

 

In my old honda, I also noticed a loss in MPG after installing a K&N. I had friends claim it improved their MPG, but in my case I lost MPG.

 

I have a K&N drop in filter for my 2008 TL and it runs fine. I am removing the resonator from the stock airbox which sits at the bottom of the bumper for a custom CAI. I have no problems with the filter. Maybe later on ill go with the secret weapon cold air intake used to have it on my old 2005 tsx

 

We're not saying that it wont run fine with a KN drop in filter. because it will.
we are saying that the factory filter is better.

 

In my opinion Id rather have the K&N drop in then the stock paper filter. I had to change the filter as it was really dirty coming from a used stock airbox. Changed from a short ram noticed i lost high end power.

 

Short rams are called HOT air rams for a reason.
because you lose power.

 

Agreed

 

just run no filter, i do

 

will you elaborate on the losing power part. how is it possible to free restriction from stock air box, with larger diameter piping and decent flowing filter (regardless of the temperature it draws from) but could easily be wrong about all this...

cold air intakes sits lower to ground and will provide cool, less dense air down the intake so more power. in the summer months when temp and humidity rise that is very is important if you want to squeeze every last pony out of your engine. summer heat is where the sri could possibly "lose" power. im far from an expert but here's my

our under hood temperatures soar at 80 degrees versus 60. i do not have any gauges or monitors but check my tb and intake tube temps by hand after driving. i've found them to be almost cold to touch most of the year, but when outside temp gets into high 70's they become extremely warm to touch. assuming the short ram uses near the same temperature outside during cold weather months. i think the difference between cai and sri would be minimal.

 

More like 160 underhood in city driving.

Sitting low to the ground has nothing to do with a CAI making power. Getting the inlet out of the engine bay is the only goal. Lower has nothing to do with it and you can argue it puts it closer to the hot asphalt.

SRI ingests warmer than stock air, why anyone would install one, I'll never know.

 

misunderstanding- I was saying the underhood temp which I don't know exact numbers, drastically increases when the outside temps reach high 70's versus say 60 outside when my throttle body and manifold stays extremely cool. it's not like the car gets absolutely no air when driving. wind travels through vents etc. and yes hot air rises so the temp of sri will obviously be higher. im not here to prove the world wrong. just don't understand where this info on sri "losing" power.

let's say intake temperature wasnt a factor. when upgrading stock air box that has numerous twist turns and chambers, to larger aftermarket piping you are going to increase the volume of air to access the engine faster. yes cool air is best for combustion and will provide better gains. unless dyno proven how can you say stock air box provides power over sri. If anything, sri loses torque over cai. aftermarket intakes allow higher volumes of air to be used.

so if someone could explain how sri are losing, minus underhood temp, that would be appreciated because it still doesn't make sense to me

 

Underhood temp is the reason why it loses power.

The factory intake tract has no restriction so throwing a larger filter and short straight plumbing does nothing. The factory plumbing is a semi-cold air intake already so a SRI is bringing in considerably hotter air. The location high or low doesn't make a whole lot of difference, just being in the engine bay vs out of the engine bay is what matters.

OEMs no longer leave anything to be gained in the inlet tract. It's free hp so they're plenty free flowing as is. The stock air filter is sized large enough so that it can be pretty dirty before it starts to restrict flow.

As for underhood temps, it's really not an argument. Plenty of us have measured temps after both freeway drives and city driving. The TB and intake manifold will stay somewhat cool until you shut the engine off due to the fresh air coming in..... as long as it's not sucking hot air from under the hood. Typical underhood temps on my car were 160+. You have two fans that pull 200+ degree air through the AC condensor and radiator and into the engine bay. That's the majority of the airflow. Then you have two catalytic converters under the hood that can run over 1,000 degrees. Around town it's cooking. On the freeway not so bad.

 

now it's making more sense to me. so if the piping on cai is smaller than sri diameter it would still make gains bc of the air temp location? guess im just upset bc my first mod was k&n short ram. but you learn something new everyday. this forum has great info in every section and i wouldn't know anything if it wasn't for people like you

 

I put in a fram filter and have better mpg by 1