K&N Filter, worth it?

[Majortom]

Actually, a Mass Air Flow sensor does not control the flow of air into an engine, but feeds a signal voltage to the Engine Control Module which determines the amount of fuel delivered to each cylinder based on the amount of air that flows across the sensor.

"the MAF will simply adjust itself to the preprogrammed volume of air feeding the injectors regardless of a freer or restricted air filter."

True to an extent. The fuel control systems used in automotive service are not truly linear, but a large series of mapped set points that engineering has plotted during testing. As originally plotted (or programmed) the fuel delivery is based on a known amount of air flow resistance in the factory system. At low air flow rates (amount of air rushing into the engine) any difference in resistance will probably not be detected by the engine computer. As air flow increases, the resistance of the air delivery system (air or filter box, ducting, etc.) has more of an effect on fuel control.

The best example of this effect is at wide open throttle (WOT). At WOT most systems expect to see, and will compensate for, the factory designed resistance. If this resistance is removed or drastically reduced, the fuel map internal to the ECM may not be able to provide the correct air-fuel mixture.

Best regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 17 July 2018. Now at: 037077 miles.

Thanks for a detailed response. Yes, was aware the MAF didn’t directly control the air flow but rather it provides the ECM readings of air mass (density) which changes due to environmental conditions (temp, altitude, and I think even humidity???) which in turn the ECM reacts to calculate the air/fuel mixture. That said, I still don’t see how an air filter alone would have an appreciable improvement in performance or fuel mileage except for in a carbureted engine. For the money, I would think something like the Pedal Commander would be a better option.

 

[Dusty1948]

I apologize if I confused anyone. I was simple trying to clarify how a MAF sensor works in a system.

Ram uses the more accurate and meaningful Speed Density System utilizing a Manifold Absolute Pressure sensor (MAP) and an Intake Air Temperature (IAT) sensor. MAP sensors are transducers which work directly with intake manifold pressure. Manifold pressure better and more quickly reflects changes in air density, air temperature and altitude.

Mass air flow systems would be considered 'quick and dirty' by todays standards. MAF sensors are typically hot wire or vane-type sensors, both are very prone to failure by contaminants.

Best regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 17 July 2018. Now at: 037077 miles.

 

[Dusty1948]

Thanks for a detailed response. Yes, was aware the MAF didn’t directly control the air flow but rather it provides the ECM readings of air mass (density) which changes due to environmental conditions (temp, altitude, and I think even humidity???) which in turn the ECM reacts to calculate the air/fuel mixture. That said, I still don’t see how an air filter alone would have an appreciable improvement in performance or fuel mileage except for in a carbureted engine. For the money, I would think something like the Pedal Commander would be a better option.

Well, there are plenty of seat-of-the-pants testimonials that contend an improvement, although most of them are making a judgement on 0-60 times and the like. There is a fellow who has done a video comparing various dry element air filter brands on the web and then done either 1/4 mile or 0-60 times (can't remember which). Even if valid the effect on gas mileage and amount of trapped dirt is still an unknown.

Of course there are reports of just the opposite.

Best regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 17 July 2018. Now at: 037077 miles.

 

[Majortom]

From the sound of it, I need to read up on the MAP. My other vehicles are a 2002 F-150 and a 2008 M35 which have the MAF. And yes, from experience they do get fouled.

 

[PowerJrod]

Did not know there isn’t a MAF on these (obviously ). Thanks for that bit of new info PowerJrod!

Anytime my friend! I actually didn't know until a couple months ago myself lol.

 

[BowDown]

I don't think I they are worth the cost for bone-stock anything. Plus, over oil them and your risking messing up the MAF sensor

FCA engines are Speed Density not Mass Air and don't have a MAF sensor

 

[BowDown]

Yeah, Dodge/Ram/Diamler/FCA have always used MAP sensors to do the job, rather than MAF, for as long as I've owned them (first was a 1995 Dakota). It probably goes for even longer before that.

All engines use a MAP (Manifold Absolute Pressure), its used to calculate Air Density such as altitude changes, BAR pressure drops and general air density from summer to winter and adjust short term fuel trims. MAF and MAP are completely different, every engine has a MAP, not every engine has a MAF, Speed Density tunes which FCA uses do not. Speed Density allows for a little more detailed tuning, my mass air Z06 was tuned with via mass air then detailed tuned with Speed Density to compensate for airflow that the computer could not be tuned for

 

[Kob0583]

I have had good luck with aftermarket filters, seen this debated for an against. I like being able to wash and reuse vs replace. I would say dry is better but oiling a filter has never been a big deal, I’ve never over done it or thrown a code. Love them hate them or don’t care but if you **** up oiling a filter you probably don’t need to be working on your truck. Always found that talking point weird is all. Dusty sounds like he knows a hell of a lot more than I do though as I never knew about MAP vs MAF. That’s what I love about forums is what you can learn.


Sent from my iPhone using Tapatalk

 

[Shives]

I'm sure this will be heresy to some.

The air filter for engines used today is designed as an integral part of the fuel delivery system. Changing the resistance to air flow will effect the delivery of fuel at various rpm points thereby altering the factory fuel mapping. How this affects engine performance can vary depending on the engine and the design of the factory induction system. There's testimony from various sources that it improves vehicle performance, and other testimony that it does not. There's at least one video of a dyno test on a Mustang where a less restrictive air filter actually reduced horsepower.

Since today's truck motors are designed to bring in power at lower rpms, a low restrictive air filter probably won't provide much if any benefit at road speeds.

Whether a low restriction air filter provides any performance benefit aside, the ability to filter out small particles is highly questionable. Much of the filtering is dependent on the viscous oil used to coat the filter. Progressively over time this oil dissipates away thereby reducing the filtering capability.

I've used these filters on my ATVs, and frankly found them to be a PITA. They've caused performance issues and increased maintenance time.

Best regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 17 July 2018. Now at: 036844 miles.

So, I do love when people compare a ATV or motorcycle to a truck.. or car.. In essence.. YES.. You changed the air filter, and now your allowing more air to enter the engine, without adding more fuel. this is a lean condition. In bikes and small engines this is very very harmful to do without tuning.. When you tune your ATV or Motorcycle properly, adding a K&N will increase power.. Proven, and beyond effective. Many say they have trouble, its due to the fact NOBODY TUNES AFTER UPGRADES... But... I've only been Dyno tuning for 10 years or so.. So much to learn. A tech for 25. ( I really like the header debates, those are fun!!)

The fact the cars, and trucks can use MAF, and or some sort of speed density sensor of sort, this does tell the engine how much air is going past a point. BUT, does not re-do the map, as much as needed. If any in this situation. You need to add fuel.. Without adding the needed fuel... Then as mentioned... This upgrade is eye candy, and a cool cleanable filter. (The gas milage debate... Thats a hard one for me. Again.. We just added more air.. in fact if the engine does allow for more fuel.. then that would be worse gas milage, better performance.. SO...if the map is too fat or rich, this would allow to use that gas better.. BUT most engines are so lean now days due to emissions) Again this also asks... Is this condition also going to cause your engine to heat up more, and dye faster.. More lean, more heat... Most folks don't know that gas actually cools the engine too.. I could debate this all day..lol

If people want to really take advantage of running a K&N, then add some more fuel! Only increased maintenance is the fact you must clean and re-oil the K&N filters.. As, this is a cost savings and 1 of the main reasons they are bought! Yea, yea.. Dusty and blah blah... well if your doing that much driving with a stock air filter off road, then you will change it more, if your doing things right.

CAI are about useless on these trucks, the air filter box from factory is really good, and flows really well.. You can make some small modifications to the air box (filter and such) but, the biggest benefit will be you can clean it, and re-use it. ( for the love of GOD, that can o oil will last you 5 years or so.. NOT 1 APPLICATION!!.. Again, all we are doing is causing a lean condition.. To some feels like "More Power". A good flowing dry filter (even Harley uses these) maybe remove the carbon filter (ehh).. Again.. Not saying that CAI are 100% useless, they provide some more flow.. Not much, unless your tuning, adding exhaust and such... its just eye candy..


Simple Ruel of thumb... This is for any combustion engine.. More air... More fuel... In other words... If you allow more air to enter the engine, you must allow for more fuel to! OR your air to fuel ratio will be ****, and you'll run like crap... May not notice this on our trucks, as much as say... a V-twin. See, with a V-twin... Super easy to RE-MAP our engines.. VP3 Dynojet, and more...

 

[Timeless]

I recently replaced mine with a green filter and removed the charcoal filter.

The stock air filter looked to be really good and I doubt the green filter is going to be much if any better.