|04-16-2010 07:55 PM|
I ran the K&N on my Rubi for about 40,000 miles. I was a believer. I checked the tube every time I serviced the fig, about every 2000 miles. I'd run a white rag down the tube to look for signs of dust getting through - none.
Cleaning too often reduces the cleaning effect - the dirt that gets stuck to it gets wet with oil and it helps catch more dirt. When it's most likely to pass through dirt is when it's real clean.
Never saw any dirt get through, but I'm a stickler to make sure it seals correctly. I always wrapped tape around where it connects to the tube and where the tube connects to the rubber boot. And whenever I cleaned it I inspected it closely with a light inside looking for leaks.
Then - one day the rag came out with dust on it - and the throttle body blades were gummy. It let me down. I couldn't find where it leaked, I trashed the filter.
I ordered and installed a True Flow - it's a foam type with a sticky stuff like oil on it. Over that I put a K&N filter screen - keeps the big chunks out.
So far so good. No dirt.
But performance wise -
When I went with the K&N instead of that restrictive airbox it was a noticable difference.
Now that I have the Trueflow I can feel it restricting. It's not as bad as the stock unit, but worse than the K&N. Where I live the roads are up and down with hills. With the stocker I rarely got it in top gear. With the K&N I rarely had to backshift. With the single Trueflow it feels like half way between.
When I "get around to it" I'm going to try running 2 of the Trueflows in parallel. It shouldn't be too hard to fab a Y connection in the tube so 2 can be attached. The only problem might be finding room.
BTW - Mas Airflow Sensors (MAF) do get oily from the oiled type filters.
But Jeeps don't have MAFs, they use a Manifold Absolute Pressure Sensor (MAP. It doubles as a MAP and Barometric Pressure Sensor. Unless you've dumped lots of oil down, they aren't affected.
When you first turn the ignition switch on, the reading is remembered by the ECM as the Barometric pressure. Once it starts, it now measures the vacuum in the manifold. It compares that to the BARO reading to analyze load.
That's why - when you go up or down in altitude very far, like 2000-3000 feet, the Jeep will seem like it loses power. Simply cycle the key off, then on - the ECM gets new BARO information and it will run much better.
Sure beats the old days with carbs!
|04-16-2010 04:14 PM|
|04-16-2010 10:09 AM|
|alstjruby03||dog whistle.laughed so hard spilled my coffee.|
|04-16-2010 09:48 AM|
Thanks for the input peeps. I guess ill try and ditch the TB spacer and see if it gets rid if the whistling. I do agree that the K & N filters are not worth the box they come in, my buddy has one on his jeep and it gives him headaches. not to mention that K&N is awfully proud of their systems at nearly 100$ more than competitors for plastic vs metal. I went with the Brute Force because of the dry filter and good reviews; although none of the reviews mentioned the new dog whistle I would be getting.
It may be in my head but I but I do think it gave the jeep a little more umph. I use my jeep to tow my flats boat and have noticed that I an not downshifting as much on inclines (we dont have hills in Fla)!
|04-15-2010 10:35 PM|
Ran one in a Subaru Wrx for years and it not only was a bi-otch to re-oil but it always screwed with my MAF because I couldn't get the oil just right, always seemed to over apply leading to re-cleaning of the filter and cleaning of the maf sensor too. I finally got sick of that and switched back to OEM intake.
Perhaps they kick ass in a rally race. Pressed hard one day off road, and then re-cleaned.
Oh yeah, and once it fell off the intake tube.... Hell, I know it was tight. Didn't slip out of the engine bay though.
|04-15-2010 08:32 PM|
Instead of tossing my 2 pennies into this discussion (again), I'm just gonna post the thread I started on it.
For you folks that haven't read it, please do.
I WAS running a well oiled/maintained K&N filter on my TJ. I offroad it. I offroad it in southern California where it's dusty. Check out the pics I posted in my link and the rest.
Bottom line, like Cavey, I don't need anymore testing or statements about how great they work on mustangs etc. Don't care. Jeep application is what I'm discussing here and in this thread: http://www.wranglerforum.com/f19/tim...ave-32892.html
|04-15-2010 05:57 PM|
|04-15-2010 01:52 PM|
NOTE NO WHERE AM I SAYING THAT FOR OFF ROAD A K&N MAY BE THE APPROPREATE OR BEST FILTER.
K&N filters started gaining popularity in the early 90's and with the birth of the internet and auto forums have spread all over the place. Many, many, many people have been using them on vehicles for many years. (And it's not just K&N, there are lots of high flow and mystery filters a lot of people are using) Where are all the failed engines or problems as as a result? If indeed with the lawsuit crazy world we live in, people would have class action lawsuits agains K&N and others brands for destroying their vehicles.
I personally have had one on one vehicle for 17 years and another for 10+. Note they are both on-road vehicles
My TJ came with a drop in K&N. The TJ is now the DD and sees some light trails a few times a year. An I worried about the K&N? No
Obviously this is a Jeep forum where there is a lot of off road so the general answer for filtration is it is not the best choice. Too many people here just drop the line that it is total junk. That is not correct. The answer when this topic comes up every week or so should be quantified to talk how it is used.
Does a K&N filter as much as some other filters? I don't know for sure. Maybe not (yea you can go to the links for "tests" people have conducted but how much and what size dirt is too much?).
Is a K&N going to destroy your motor overnight on the street? No. A K&N is fine for the street.
Is it going to destroy it over a long time on the street? No.
Is it going to cause wear over a long time? Maybe but not to the point that the engine is going to drop dead and fail.
Is it going to degrade performance? I don't know. I have not seen supporting data.
Is it fine if you off road some/a lot? I can't say but it probably is not the best choice.
|04-15-2010 12:21 PM|
|04-15-2010 12:17 PM|
|04-15-2010 12:09 PM|
|04-15-2010 11:04 AM|
My 04 Rubicon came with the AEM Brute Force and throttle body spacer so I don't know any different. But I know I don't like the maintenance involved with the oil type filter. I purchased the dry flow filter as soon as I found out it was available for the AEM Brute Force system. In fact according to AEM this system was designed to be used with the dry flow air filter.
But according to rrich It doesn't matter how much you oil the filter for a Jeep. You won't have problems with a MAF.
I'll definitely keep the oiled filter for back up.
|04-15-2010 10:24 AM|
I have a cheapo Vatozone filter on my rig, but there is very little left of the engine bay. It sounds like a jet when I fire it up, but other than that, it is fine.
On my wife's 06 Mustang GT, I have the AEM Brute Force and throttle body spacer, and it REALLY woke it up. No other changes in anything, but you can feel the difference.
Here is my engine bay on the TJ....I am in the process of a D60 front swap and a 7" front stretch with coilovers and full hydro steering.
|04-15-2010 08:03 AM|
|04-15-2010 07:31 AM|
|cavediverjc||I don't think it's so much the people complaining about the element getting dirty so fast, but the dust that collects in the tube downstream from the filter. K&N's are junk. Plain and simple.|
|04-15-2010 05:24 AM|
No, not under normal circumstances. Mixture is sensed, then controlled by the O2 sensors and computer. The only time anything is affected is when the engine "demands" more air and fuel. That's at WOT and high to medium R's (like going up hills.) Even then, mixture - the ratio of air and fuel - isn't appreciably affected.
The restrictive air inlet limits the total amount of the mixture the same as if the fuel was restricted. Restricting either affects power during those times.
In the days of non-computerized carburetors it did affect A/F mixture. But modern day computers compensate for it.
Oil is a very good way to capture dust, even the very small dust particles. The old military Jeeps used oil filled air filters, as well as many modern day pieces of equipment.
The problem With K&N, in my opinion, is it only has one layer of filtration. I'd like to see them make one with at least 2 layers separated by a space.
He He - some people complain that K&Ns get dirty too fast. Does that mean they'd rather have that dirt go through the paper element so the filter stays clean? If that's the case, they'd be better off putting their air filter in their bedroom where there isn't much dust (well, maybe not as much.)
|04-14-2010 10:41 PM|
Nice! did not know that.
However, to much air restriction or to little must effect the firing mixture , no?
|04-13-2010 01:29 PM|
|04-13-2010 11:52 AM|
One came installed on my 04 Rubicon that I reciently purchased.
I removed the AEM oiled air filter that was attached to it and replaced it with the AEM dry flow air filter. The Dry Flow Air Filter is a good way to go. Easy to Clean and no oiling required. I was somewhat surprised to find a oiled air filter attached to the AEM intake since the Brute Force Systems are designed for the Dry Flow Air filter element.
I had a K&N ram air system, both Ram Air and a Cold Air configuration on a Subaru WRX. It was a pain to keep the Air Filter oiled and if you oiled too much the engine would choke and I would have to remove it re-clean it and re-oil it with less oil just about each and every time after a cleaning. I usually had to clean the MAF too of exsissive oil getting on it to clear the check engine light.
With a ram air intake system the whining noise while accelerating is normal. Sometime a flutter like noise will be heard with certain ram air intakes.
|04-13-2010 11:00 AM|
Most likely the noise is created by the TB spacer. The purpose of them is to help mix the fuel with the air -- but TJ's don't don't have fuel up there, it's injected down by the intake valve. The added turbulence created by it may even be detrimental. (Turbulence is also a restriction.)
You'll still get some sucking noise from the lower restriction air intake - now you know why Jeep uses that long resonant tube, the big resonant chamber box, and draws air in through that tiny hole behind the headlight. It's all there to dampen the intake noise.
The general consensus is it makes no difference, but get used to the low restriction intake, then go back to the stock box. You'll hate it.
Idling, cruising etc., the lower restriction intake will make no difference. Where you will notice a difference is on hills in the street - the ones where you had to backshift before and now you don't.
Since you don't spend all your time just going up hills and never down, You won't notice any change in mileage.
|04-13-2010 10:44 AM|
|alstjruby03||mine does it also when i put my foot in it.it is anoying.|
|04-13-2010 08:34 AM|
i get the whistle about 2k rpms
only reason i have one b/c of my on board air
|04-13-2010 08:15 AM|
The whistle is most likely from the TB spacer. They are known to do that.
As indicated above, a CAI and big open element filter has no benefit on the TJ motor for HP or mpg. (It can have some HP benefit on other vehicles. Zero mpg benefit anywhere). And dependig on how you use you TJ, it may not be the smartest addition if you off road in dusty conditions a lot or encounter a lot of deep water.
A TB spacer is utterly useless on any fuel injected motor.
|04-13-2010 06:59 AM|
|cavediverjc||That seems to be the general consensus. Unless you're installing tube fenders that require an aftermarket air intake assembly, there doesn't seem to be much of a benefit to installing one.|
|04-13-2010 02:31 AM|
|pokey||Hopefully you kept your stock air intake. The aftermarket air intakes are no improvement over the stock unit. Not better gas mileage, not better performance. Go back to your stock setup. Especially if it's bugging the hell out of you.|
|04-13-2010 12:41 AM|
anyone have an AEM Brute Force air intake system installed?
I recently installed an AEM Brute Force Air Intake system on my 99TJ and was wondering if anyone else with this system gets a whistling noise under acceleration. At a steady speed i dont get it, but as soon as i give it a little gas and accelerate, I get a whistling sound that lasts for a couple seconds then goes away. I cant get it to do it while parked and reving the engine but when driving, if you give it a little gas or "bounce" the throttle it will do it every time & whistle a bit while accelerating; its bugging the hell out of me quite frankly It reminds me of when you have a lose fan belt and it squeels under acceleration, only mine is a whistle and it only last a few seconds thankfully. At first i though that I possibly didnt get one of the hose clamps tightened good enough and it was sucking air (no pun intended) but that unfortunately wasnt the case. I have a flomaster exhaust system with headers so it gets masked quite a bit but I can imagine that it would be quite annoying and quite noticeable to someone with a quieter stock exhaust system. installing one of these systems isnt rocket science and there isnt much to it other than some hose clamps and the 4 bolts for the throttle body spacer. Let me know your thoughts please, im tired of my jeep "singing" when on the throttle....................