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I am debating if I should be a K&N airfilter replacement for the standard RT airfilter. Anyone have any opinions on this? Is it worth $50? I have bought them a few times, but have always seemed to buy them not long before selling the car. This time I was going to be proactive and buy now just having bought my RT a few months ago.
 

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No, in one of the CAI intake faceoffs over at LX, they found an actual decrease in HP.
 

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I am debating if I should be a K&N airfilter replacement for the standard RT airfilter. Anyone have any opinions on this? Is it worth $50? I have bought them a few times, but have always seemed to buy them not long before selling the car. This time I was going to be proactive and buy now just having bought my RT a few months ago.
Any high flow filter will be better than the stock air filter. I am getting ready to do some comparison testing on various drop-ins on my SRT. So far I have bought the AFE, K&N, and the Fram Airhog. I haven't done all the performance testing yet but here are the surface area comparison numbers and my costs from Amazon (not including shipping):

AFE 318.5 sq. inches ($35)
K&N 399.0 sq. inches (+25.3% over AFE) ($47)
Fram Airhog 489.4 sq.inches (+53.7% over AFE) ($12)

The stock SRT airbox will only accept the K&N filter due to a notch in the upper right corner that requires other filters to be modified to fit (the R/T airbox will accept them all-no notch). I am currently running the K&N and can feel the difference over stock. I modified a Fram Airhog last year and was quite impressed with it and think it felt better than the K&N. I am buying an R/T lower airbox so that I can do a better comparison using 1/4 mile performance and dyno testing as the measure.

Long answer to your question, but maybe info this helps.
 

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there is no claim anywhere that a drop in filter increases power, only the intakes. this has been discussed a million times.


- a drop in will decrease hp
- a drop in does not increase power or fuel economy
- a filter doesnt increase airflow if the throttle body can already get all the air it needs out of the stocker (aka, 400cfm throttle body with 500cfm stock filter doesnt matter if you put a 700 cfm filter in)
- k and n is junk and i wouldnt use it for anything other than toilet paper
- the only only only advantage out of a junk k and n over stock is reusability- with the assumption that you oil it correctly which 80% of the people out there with them dont
 

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I can't see it decreasing anything based on what the stock filter looks like... I use a K&N btw and will continue:beerchug:
 

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ask every ******* thats ever gone to a dyno. You know how many goofy ol white guys i see pull a k and n out the box and replace the stocker on the dyno? how many times the local crew laughs at em? and howmany times out of 100 they get pissed when they see a decrease in power average about 2-3 hp on a 300 hp vehicle?/ Its hilarious, i see it all the time. And sure as hell dont watch it on a ram. those guys get so mad at the near 5 hp loss that they defile them in ways my 3 year old son should never see. They hamper air flow.


think about it. they advertise a increase in power. Now anyone that knows simple modification mathmatics knows these formulas

+ power - mpg
or +mpg - power

period, not both, (other than removing cats)

theres a reason 85 hp corrollas make better gas mileage then a f250 super duty.


Now ya, theres always the mod or two that may do both but its extremely rare and normally only when you alter a emissions device which is a resistance in the system anyway

tstat - lower gas mileage
boost-lower gas mileage
diablo- lower gas mileage
cam-lower gas mileage
stroker-lower gas mileage


see the trend?

people need to realize how much engineering goes into these cars. do you not think if ford/dodge could get 3 mpg improvement by using a 3 dollar e3 crap plug or k and n filter for 40 bucks they would not do it? they are struggling like crazy (ford to keep the gt/mustang/svt, dodge, the viper , challenger srt) to keep those hot cars they have to average 35 mpg over the line up

so for dodge to keep the viper at 9 mpg they have to have x amount of vehicles over 35 mpg to average that 9mpg up to 35.
so the average of avenger, caliber, charger, challenger, viper all have to have a average of 35mpg. If chrysler could put the wonderful e3 lawnmower plugs in and get an improvmen they would. However since the product is crap they dont.
 

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there is no claim anywhere that a drop in filter increases power, only the intakes. this has been discussed a million times.


- a drop in will decrease hp
- a drop in does not increase power or fuel economy
- a filter doesnt increase airflow if the throttle body can already get all the air it needs out of the stocker (aka, 400cfm throttle body with 500cfm stock filter doesnt matter if you put a 700 cfm filter in)
- k and n is junk and i wouldnt use it for anything other than toilet paper
- the only only only advantage out of a junk k and n over stock is reusability- with the assumption that you oil it correctly which 80% of the people out there with them dont
I don't know if they do anything or not but I plan on doing my own testing and satisfy my own curiosity.

As for no one claiming that a drop in increases HP check out this 14 RWHP claim and dyno test by HotRod magazine...

http://www.hotrod.com/multimedia/ho...ger-srt8-k-n-engineering-dyno-test/index.html
 

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a filter doesnt increase airflow if the throttle body can already get all the air it needs out of the stocker (aka, 400cfm throttle body)
For all the math fans out there, the stock SRT airfilter has a max air flow of 5500L/min. That's just 193 cfm. (~28.4L/cf). I think that makes it restrictive.

Here's a pic of the 5500L/min label on the filter:
 

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Ddaddy,

If you are going to do a comparison, you may also want to evaluate the Greenfilter. Adding this to your comparison would be informative.

How do you plan to evaluate them by the way?

www.Greenfilterusa.com

Really good flowing filter.

Brian
BND Automotive LLC:bigthumb:
440-821-9040
 

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For all the math fans out there, the stock SRT airfilter has a max air flow of 5500L/min. That's just 193 cfm. (~28.4L/cf). I think that makes it restrictive.

Here's a pic of the 5500L/min label on the filter:
so there is one of two options here.
say the filter has a max 193 cfm as posted
either

a/ the throttle body flows nowhere near that stock and the engineers all have brains that there masters degrees in mechanical engineering can back up. Hence it dont matter if you put a 1000cfm air filter in there if the throttle plate is 90cfm
or
b/ the engineers are stupid and put a big rock in the intake system to degrade the power of the top of the line performing vehicle when they could have just put a better filter in there for 10 bucks more.

Not trying to be harsh but this subject has been done so many times (probably 200 + on this forum) it just gets old repeating stuff and trying to help people when in reality noone gives a ship because they will buy whatever horsepower tv told them too on sunday.
You know horsepowe tv used to advertise splitfire spark plugs too but noone seems to remember that. Magazines and shows just advertise whatever the hell sponsors the show. this whole industry is filled with sell outs.
-dodge doesnt car about mobil- they paid for the advertising spot on the cap
-ford doesnt car about bp- they paid for the advertising spot on the cap
-horsepower tv doesnt really love e3 plugs, they paid for the spot
-car and driver doesnt just happen to love the top 5 cars of the same companies that are advertised on the next 4 pages.
Now if you guys dont mind, i'll take my afe beanie cap and go to bed :grin:
( i love afe)

no not really




p.s. i was thinking about starting a filter showing all the k and n filters i destroy and throw away at work. This thread is gonna push me to do that. i throw a good 10-15 away a week and there's no more orgasmic feeling
 

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Ddaddy,

If you are going to do a comparison, you may also want to evaluate the Greenfilter. Adding this to your comparison would be informative.

How do you plan to evaluate them by the way?

www.Greenfilterusa.com

Really good flowing filter.

Brian
BND Automotive LLC:bigthumb:
440-821-9040
I plan on doing 1/4 mile runs with the various filters (3 runs/filter with a 10 min run out between filters to reset the adaptives) all on the same night with the same track conditions. I also plan on doing dyno pulls with each filter with a similar run out between filters. I haven't decided how many replicates to get the data right but it will folllow a basic Design Of Experiments (DOE) protocol. I will consider adding the Green Filter to the tests (I have been looking at it anyway). It may take some iteration on the testing to get conclusive data, but hey, I'm going to be driving the beast anyway and this just adds to the fun. As always, suggestions are welcome! :bigthumb:
 

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unfortunately in my opinion the track is not gonna work. too many variables.
temp changes
fuel level/pressure changes
launch changes
weather changes
tire pressure changes
engine temp changes
driver changes
blah
blah
blah

i'd say a dyno but you'd really have to average 3 runs per filter because almost every time you change a filter on the dyno you will get a skewed line the second time. The vehicle adapts to many many parameters and when you throw a new filter in airflow changes and therefore fuel also must change.

you'll get a smooth line (assuming you have a decent parameter set up when you arrive) then you'll swap and get at least one run of wavy crap that will be down a few hp for sure. as the line cleans up and adaptives adapt(which requires several things such as decels, accels, temp changes and things done on a road basically) you'll get a few ponies back as the adaptives adapt.

You should try doing a fuse pull like everyone recommends on the dyno. :grin: the next dyno will be down 10-15 hp and look like someone peed on the chart :lol:it'll be all over the place

good luck

my guess if you had all the filters (and this has been done with intake systems before but i dont know about just filters)

first place
no filter
2 place-trueflow
3rd- green
4th- stock
5th- k and n

Taking bets?
 

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unfortunately in my opinion the track is not gonna work. too many variables.
temp changes
fuel level/pressure changes
launch changes
weather changes
tire pressure changes
engine temp changes
driver changes
blah
blah
blah

i'd say a dyno but you'd really have to average 3 runs per filter because almost every time you change a filter on the dyno you will get a skewed line the second time. The vehicle adapts to many many parameters and when you throw a new filter in airflow changes and therefore fuel also must change.

you'll get a smooth line (assuming you have a decent parameter set up when you arrive) then you'll swap and get at least one run of wavy crap that will be down a few hp for sure. as the line cleans up and adaptives adapt(which requires several things such as decels, accels, temp changes and things done on a road basically) you'll get a few ponies back as the adaptives adapt.

You should try doing a fuse pull like everyone recommends on the dyno. :grin: the next dyno will be down 10-15 hp and look like someone peed on the chart :lol:it'll be all over the place

good luck

my guess if you had all the filters (and this has been done with intake systems before but i dont know about just filters)

first place
no filter
2 place-trueflow
3rd- green
4th- stock
5th- k and n

Taking bets?
OK, let's try it this way. You are an automotive design engineer being paid $150K to evaluate different drop-in filters on the performance of a 6.1L SRT-8 with 53K miles on the clock. Your personal bias or opinions are not permitted to influence the test nor are you allowed to make any predictions about the results. What is your experimental design to get conclusive data on the various filters and the resulting performance?
 

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I have a drop in k&n on my Charger and have no compaints. As for gas mileage, horsepower +/-, I'll let you know after I put the cam in my truck. I am betting that I get better mileage on the freeway while gaining decent time at the track. The cam is going in on saturday, if this thread is still around I will post up what I come up with. I totaly disagree with the adding horespower lowers mileage, unless you are only measuring WOT.
 

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OK, let's try it this way. You are an automotive design engineer being paid $150K to evaluate different drop-in filters on the performance of a 6.1L SRT-8 with 53K miles on the clock. Your personal bias or opinions are not permitted to influence the test nor are you allowed to make any predictions about the results. What is your experimental design to get conclusive data on the various filters and the resulting performance?
Here is a good article that should be shared.

http://www.geocities.com/dtmcbride/products/air_filter.html

Gives some background and types and their results.

Regards,

Brian
BND Automotive LLC
440-821-9040
 

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there is no claim anywhere that a drop in filter increases power, only the intakes. this has been discussed a million times.
K & N claims increased power on their home page.

Designed to increase horsepower and acceleration while providing excellent filtration
Lifetime air filter with K&N Million Mile Limited Warranty®
The World's Best Air Filter
Simple drop-in performance


Taken from here. http://www.knfilters.com/
 

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K & N claims increased power on their home page.

Designed to increase horsepower and acceleration while providing excellent filtration
Lifetime air filter with K&N Million Mile Limited Warranty®
The World's Best Air Filter
Simple drop-in performance


Taken from here. http://www.knfilters.com/
And that stupid chip claims 75hp gain and 3 mpg
 

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OK, let's try it this way. You are an automotive design engineer being paid $150K to evaluate different drop-in filters on the performance of a 6.1L SRT-8 with 53K miles on the clock. Your personal bias or opinions are not permitted to influence the test nor are you allowed to make any predictions about the results. What is your experimental design to get conclusive data on the various filters and the resulting performance?
I am (or was) and automotive engineer and in the past managed a 10 bay dyno test facility. Chrysler has done a decent job balancing the intake flow, and not much you can do to improve it. Nick is correct, there are way too many variables on the track to measure a measly 10-20 hp differential. You might be able to do multiple runs on the dyno and see some trends. LX Forums has done at least a couple of faceoffs and they have controversy about the test methods, products, and just general whining. They try to limit the variables, but that's difficult.

To answer your question, and Nick will have a hissy fit, one way to take out the adaptives (which Mercedes messed up big time), is to pull the fuse before every run, setting the system back to default. BUT, adaptives very quickly "adapt".

IMO, the CAI for stock or mostly stock engines is more about the sound then any actual performance improvement.
 
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