C.A.I. Horsepower Gains

[427435]

The biggest gain is noise at WOT. Most cars today (I haven't looked at the Genesis set-up) already pull their air from somewhere in front of the radiator (at least my 03 Vette and 03 Explorer do and my 04 Mercury Marauder did). As for filtering, I still remember what an engine lab supervisor told me about engine life. He said it shouldn't be measured in hours or miles, but in how many grams of dust/dirt it has ingested.

As for filtering efficiency, read this test (there are very sophisticated machines to do this testing):

http://www.scribd.com/doc/23641356/ISO-5011-Duramax-Air-Filter

One of the more interesting statements from this test is:

After only 24 minutes the K&N had
accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly
3 times faster, passed 18 times more dirt and captured 37% less dirt.

As for race cars, it's been a long time since I've seen anything but big paper filters on them--------especially dirt track cars.

 

[zielritter]

The biggest gain is noise at WOT. Most cars today (I haven't looked at the Genesis set-up) already pull their air from somewhere in front of the radiator (at least my 03 Vette and 03 Explorer do and my 04 Mercury Marauder did). As for filtering, I still remember what an engine lab supervisor told me about engine life. He said it shouldn't be measured in hours or miles, but in how many grams of dust/dirt it has ingested.

As for filtering efficiency, read this test (there are very sophisticated machines to do this testing):

http://www.scribd.com/doc/23641356/ISO-5011-Duramax-Air-Filter

One of the more interesting statements from this test is:

After only 24 minutes the K&N had
accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly
3 times faster, passed 18 times more dirt and captured 37% less dirt.

As for race cars, it's been a long time since I've seen anything but big paper filters on them--------especially dirt track cars.

The 3.8 has a very odd set up in stock form. The box splits - one tube opens up in front of radiator and points forward (good).

The second tube has a magnetic flap that probably opens up a certain intake pressure and is between the engine and radiator. Both of these tubes have sharp angles, are lined with a coarse carpeting (to reduce noise at the expense of a bit more restriction), and one opens open directly to hot air. The main tube that runs from the box to the TB has two fairly large resonator boxes, which also create restriction.

I tried to do my homework when I built my intake. I didn't want to just rip out the stock system if it looked nonrestrictive, but it's clear that Hyundai wanted this engine to be as quiet as possible. If there's 10-15 ponies to be had by opening up the intake and installing a freer flowing system, then I'll do that because I can live with the extra noise at WOT. Same goes for the exhaust.

I've read all about the cotton oiled filters and know that they filter worse - many studies that show this, but those same studies show a better flow rate. I figure if I clean my regularly and use quality engine oil changed frequently, I'll be fine.

 

[radicaltimes]

Most of what everybody things is gain is just additional noise. Go to a dealer and look at the intake for a 505 hp Corvette. It is only about 1 1/2" high and 6" inches wide where it goes over the radiator support.
I remember when I used to turn over the cover on my air cleaner on my 1968 Camaro. Sure sounded like I was going faster

 

[garner]

Sorry but on certain cars cai do show dyno proven gains after a tune. Tune being key word though. Most untuned cai don't do much but extra motor noise as others have said which is a nice feature but to get the power you need a tune

 

[ShadowScoobySTi]

Isn't it true that the 8spd transmission is only rated up to 450hp? I'm not sure if that is accurate, but I remember reading about that on the net. Anybody know the actual max rating of the transmission?

 

[zielritter]

Isn't it true that the 8spd transmission is only rated up to 450hp? I'm not sure if that is accurate, but I remember reading about that on the net. Anybody know the actual max rating of the transmission?

I read that too somewhere (maybe here), but can't confirm. Also don't know if that's 425whp or bhp.

 

[427435]

The 3.8 has a very odd set up in stock form. The box splits - one tube opens up in front of radiator and points forward (good).

The second tube has a magnetic flap that probably opens up a certain intake pressure and is between the engine and radiator. Both of these tubes have sharp angles, are lined with a coarse carpeting (to reduce noise at the expense of a bit more restriction), and one opens open directly to hot air. The main tube that runs from the box to the TB has two fairly large resonator boxes, which also create restriction.

I tried to do my homework when I built my intake. I didn't want to just rip out the stock system if it looked nonrestrictive, but it's clear that Hyundai wanted this engine to be as quiet as possible. If there's 10-15 ponies to be had by opening up the intake and installing a freer flowing system, then I'll do that because I can live with the extra noise at WOT. Same goes for the exhaust.

I've read all about the cotton oiled filters and know that they filter worse - many studies that show this, but those same studies show a better flow rate. I figure if I clean my regularly and use quality engine oil changed frequently, I'll be fine.

I wonder if the controlled intake to the warm side of the radiator is something for cold weather start-up. Old carbureted cars used to have a vacuum/temperature controlled hose that went from the air cleaner to near the exhaust manifolds.

You don't need that for smooth running with fuel injected cars, but maybe it reduces emissions during engine warm-up. Just thinking out loud.

 

[Philth]

I've read all about the cotton oiled filters and know that they filter worse - many studies that show this, but those same studies show a better flow rate. I figure if I clean my regularly and use quality engine oil changed frequently, I'll be fine.

Changing your oil every day won't stop the damage done in the cylinder and ring area from minute dust/dirt getting past the filter.

But, I understand your perceptive if performance is your top priority.

 

[zielritter]

Changing your oil every day won't stop the damage done in the cylinder and ring area from minute dust/dirt getting past the filter.

But, I understand your perceptive if performance is your top priority.

Understood, but I also refer back to all of the anecdotal accounts of people who have driven well over 100k miles using K&N filters since day 1 and have done so on multiple cars without issue.

If a cotton gauze filter does decrease engine longevity through letting in an increased number of particulates, is it reduced to the point that most owners should really be concerned? I guess it all depends how long you plan to keep your vehicle. Given my track record, I won't have this vehicle past 100k miles.

 

[QuantumRift]

As I've seen references to this "report" in a couple of different forums I frequent, I decided to ASK K&N about this "report"; I got a response this morning, which I am putting here VERBATIM:

============================================

Dear Doug:

That is known online as the Spicer Report and we have seen this "test" multiple times when someone is trying to defend why they do not want to go with one of our filters. Unfortunately the test is old and we disagree with the results and how it was run. When it first came out we sent a letter to Mr. Spicer about his "test" results (see below). We did not receive a response defending the test or an explanation to our questions; something we hope our customers will think about. We know our filters will filter the way your engine needs a filter to, so much that we have posted the flow, filtration and capacity tests to our filters on our website.

As a side, I would request that my e-mail not be posted in any forums; rather if the question comes up, please direct users to contact K&N directly or look at each specific filter’s test result.

For comparison, here are links to the test results for the filters specific to the Genesis cars:

33-2426: http://www.knfilters.com/dynocharts/33-2426.pdf
33-2427: http://www.knfilters.com/dynocharts/33-2427.pdf
33-2482: http://www.knfilters.com/dynocharts/33-2482.pdf
33-2958: http://www.knfilters.com/dynocharts/33-2958.pdf

Here is the letter we sent to, and did not hear back from, Mr. Spicer:


Arlen;

I have reviewed the report that you posted and am quite puzzled over the following statements. I have added my questions following each and hope you will take the time to respond back to me.

“So, according to lab work compliant to ISO 5011, the K&N product showed performance that was significantly improved over the Testand results. So, which results are more accurate, the K&N and Southwest Research results or the results in our study? The answer to this question is not an easy one. Essentially, the results of the K&N lab results and Testand’s results are both valid and at the same time cannot be directly compared for many reasons.”

You mention that the K&N was significantly improved yet you do not comment that the “paper” filter test efficiencies were nearly the same as the Testand results.??

“K&N tested the filters under a much lower initial dirt feed rate of 0.25g/cu. meter for the first 60 grams of dirt and then completed the test at 1.0g/cu. meter for the remainder of the test. Testand, on the other hand, ran the entire test at 1.0g/cu. meter (9.8g/minute at 350 cu. ft/ minute). The implications of this may be speculative, but I would have to conclude that a slower initial feed rate to a clean filter could improve it’s initial efficiency%. This would lead to an improved overall filtering efficiency when compared to a filter tested under a more demanding initial feed rate as was the case with the Testand testing.”
Since both the paper and the K&N were tested at the same feed rate during testing at K&N, why would the paper filter efficiency not change more than a couple tenths of a percent, yet the K&N change significantly, nearly two percent? The answer here is they would not. We have chosen to continue testing at the lower initial feed rate because we feel it is a more demanding test because loading the filter faster could raise the efficiency.
In fact if you compare K&N’s test to Testand’s, the paper filter passed more than twice as much dust in K&N’s initial phase, at the lower dust feed rate, than it did in Testand’s full life at the higher rate. (1.01 grams vs. 0.4 grams)?????
This is a topic we discussed at length during your visit as it was your opinion coming here. You left here with test reports showing it was a misconception. Many times our testing has shown us that what we thought was going to happen or seemed logical, was wrong.


“With variable flow testing the filter experiences a continuous change in differential pressure resulting in a “capture and then release” of the dirt particles within the test media. According to an independent testing facility, variable flow testing is a more challenging test for filter medias and will commonly result in significantly lower efficiency numbers.”
This statement, “capture and then release” holds some validity for dry paper media but not for “oiled” media. As you observed here during testing, the test dust on a K&N filter stays in place very well unless shaken or tapped to knock it loose. But again, why weren’t the efficiency numbers different on the paper filter as a result of the Variable Flow vs. Constant Flow??


“The Testand test employed variable flow testing. The K&N test employed constant flow testing. Again, both test are ISO 5011 compliant. However, given the differences in testing methods the two results are in no way directly comparable.”
See above.

Another very important point I am surprised you missed or did not mention is that the initial efficiency of both filters was within .08 percent of each other. This is significant in that from 15 to 25 percent of a filter’s life, in the real world, is in the initial efficiency segment.
We discussed at length the desire of both of us was to provide the facts enabling people to make informed decisions about products and what is best for them.

I look forward to your reply.


If you have any further questions, please reply to this email or call our Customer Support Team at 800-858-3333

Thank you for choosing K&N Engineering

James Johnston
Product Specialist
K&N Engineering Inc
www.knfilters.com
Phone: (800) 858-3333

===============================================

...As for filtering efficiency, read this test (there are very sophisticated machines to do this testing):

http://www.scribd.com/doc/23641356/ISO-5011-Duramax-Air-Filter

One of the more interesting statements from this test is:

After only 24 minutes the K&N had
accumulated 221gms of dirt but passed 7.0gms. Compared to the AC, the K&N “plugged up” nearly
3 times faster, passed 18 times more dirt and captured 37% less dirt.

As for race cars, it's been a long time since I've seen anything but big paper filters on them--------especially dirt track cars.

______________________________

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[Top Gear]

I'm not sure if this applies to the Sedan, but consider this. The Coupes all have a very good CAI that is very hard to improve upon, as many modders have found out (but won't admit). For the 10-12 3.8 V6 Coupes in the US (not sure about the 13s), there is a low-restriction paper air filter and a secondary carbon filter next to each other in the airbox. The carbon filter is there to prevent gas fumes escaping back out, per the EPA. Removing that filter is easily a 10hp/20lbs or more "mod" with no downsides. The stock filter in these US cars is just as free-flowing as a K&N, so why bother with the problems a K&N brings. I did this on my car not too long ago and I was so pleased with the results I won't need any further mods...or not yet, anyway

 

[QuantumRift]

First there is no "problem" with K&N filters. I've used them on every car/suv and motorcycle I own for 12+ years now with no issues. See previous message from K&N. No warranty voids; the engine won't seize like it had Cash for Clunkers destructo dropped in the engine (replacing the engine's oil with sodium silicate, more commonly known as liquid glass. When the car is run with a mixture of water and sodium silicate the liquid quickly evaporates and the solids are left behind, causing most of the oiled surfaces to seize and break.)

As for a 10 or 20 HP gain by removing a 'carbon' filter, that appears to be morphing into somewhat of an urban legend, here and other forums.

As I've said about the K&N, I did not buy it for any HP gains as I know that any such gain would be very modest at best and unmeasurable by my Butt Dyno. I buy K&N filters because they SAVE ME MONEY over time, and I can always have a clean filter in my vehicle (clean 'em twice a year instead of buying paper filters and discarding them).

If somebody REALLY would like to see what a K&N does, then perhaps here is how to do it:

Prior to installing a K&N filter, perform an oil and filter change to your preferred oil.

At say, 5,000 miles, have an oil analysis done and note the results.
You will also know how contaminated your oil is and whether or not you can go further on an oil change. Or even be alerted to other possible problems.

Now, change the oil and filter again with the same grade oil and new filter.
Install a K&N Air Filter.
Drive 5,000 miles and have another engine oil analysis done.

IF any extraneous particulate matter has gotten into the engine it will get into the oil and the analysis WILL show it.

That's the way to 'test' the K&N filter against an OEM filter.

A friend had a Ford Focus, I think it was, and he started doing oil analysis on it soon after he bought it. On the first test it indicated excess silica in the oil, which can only come by the engine ingesting it in the air. Well, he changed air filters, and checked things, and went on. Next oil change, he had another one done, and it kicked back same results. Apparently there was something amiss... Well, it turns out that there WAS an ill fitting part on the intake system, pretty hidden and unseen that was sucking unfiltered air into the engine. Had it gone on, it would have caused damage. But the oil analysis alerted him to the fact, and a thorough and complete inspection/examination of the intake system discovered it and allowed him to fix it.

For what it's worth.

I'm not sure if this applies to the Sedan, but consider this. The Coupes all have a very good CAI that is very hard to improve upon, as many modders have found out (but won't admit). For the 10-12 3.8 V6 Coupes in the US (not sure about the 13s), there is a low-restriction paper air filter and a secondary carbon filter next to each other in the airbox. The carbon filter is there to prevent gas fumes escaping back out, per the EPA. Removing that filter is easily a 10hp/20lbs or more "mod" with no downsides. The stock filter in these US cars is just as free-flowing as a K&N, so why bother with the problems a K&N brings. I did this on my car not too long ago and I was so pleased with the results I won't need any further mods...or not yet, anyway

 

[Top Gear]

The carbon filter deletion trick is no more an urban legend than a K&N filter upgrade, far less so, and costs nothing to try.

My point was that for the 3.8 Coupe in the US (and perhaps other cars), the stock paper filter is actually close to a K&N in terms of air flow - but for that carbon filter cancelling it out. 3.8'ers who switch to a K&N report no change whatsoever, until they remove the carbon filter in this car. The two filters are designed to work together to be like a single normal filter but with added fume prevention. Removing the carbon filter and using only the stock thinner-style paper filter already in there gives you the same or better performance benefit as would switching to a K&N for a car with no extra carbon filter from the factory. I assure you, removing it was enough of a Butt Dyno boost for me to rave about it, especially on low-end torque and throttle response.

The K&N "problems" I referred to are the oiling/drying out some people seem to have with K&N filters, or the potential questions one might get from a particular dealer in a warranty claim situation. Either problem might be moot with proper care of the filter or a more laid back dealer, but need to be considered, whereas staying with the 3.8 US Coupe filter is worry-free and regularly replaced same-for-same if serviced by the dealer. The dealer is unlikely to notice the carbon filter missing because of where it is, but even then it's easily replaced or explained away.

Otherwise, I've got no problem running a K&N or other aftermarket filter

 

[QuantumRift]

There wouldn't be any 'warranty' situation with a K&N filter due to the legal issues covered by the Magnusen-Moss act of 1975 ( http://www.tundraheadquarters.com/blog/after-market-accessories-new-warranty/ )

K&N has their ducks in a row on this issue: "When you buy an OE replacement K&N High-Flow Air Filter or High-Flow Air Intake System you can be confident your vehicle’s warranty will remain in effect. If you experience a difficult dealership, K&N will resolve the issue so you won’t have to. We believe K&N makes The World’s Best Air Filter and we stand behind that claim 100 percent." But we all know this.

Yea, I DO not have a 3.8 coupe (though I'd like to!).

Are there any hard and fast dyno results on this? I know what the claims ARE; but its absolutely "interesting" that the simple removal of an activated charcoal element (filter) that essentially only absorbs unburnt hydrocarbons backflowing through the intake would "add" such HP or mpg gains. If car manufacturers are 'struggling' or working hard to get their fleet mpg averages up, it seems odd that this method (using the filter) would 'bog' down an engine so much when other, less 'taxing' methods could be utilized. Amazing.

I use K&N for longevity, that's all. For example, an OEM Suzuki filter for my Suzuki Burgman 650 costs nearly $40 w/ tax. The K&N equivalent cost me about $52. That was almost 3 years ago. Based on ONE filter a year, that puts me on the plus side.

The carbon filter deletion trick is no more an urban legend than a K&N filter upgrade, far less so, and costs nothing to try.

My point was that for the 3.8 Coupe in the US (and perhaps other cars), the stock paper filter is actually close to a K&N in terms of air flow - but for that carbon filter cancelling it out. 3.8'ers who switch to a K&N report no change whatsoever, until they remove the carbon filter in this car. The two filters are designed to work together to be like a single normal filter but with added fume prevention. Removing the carbon filter and using only the stock thinner-style paper filter already in there gives you the same or better performance benefit as would switching to a K&N for a car with no extra carbon filter from the factory. I assure you, removing it was enough of a Butt Dyno boost for me to rave about it, especially on low-end torque and throttle response.

The K&N "problems" I referred to are the oiling/drying out some people seem to have with K&N filters, or the potential questions one might get from a particular dealer in a warranty claim situation. Either problem might be moot with proper care of the filter or a more laid back dealer, but need to be considered, whereas staying with the 3.8 US Coupe filter is worry-free and regularly replaced same-for-same if serviced by the dealer. The dealer is unlikely to notice the carbon filter missing because of where it is, but even then it's easily replaced or explained away.

Otherwise, I've got no problem running a K&N or other aftermarket filter

 

[Philth]

Playing devil's advocate here...

If K&N filters are so great, then why aren't ANY OEMs using them?

 

[QuantumRift]

To just kind of respond:

1) The average schlep who buys a car doesn't want to have to fart around with recharging an air filter once a year or so. Kind of messy and not everybody wants to deal with it. Some people might even get PO'd if it was installed and they were not told about the upkeep on it. Even though it saves them money, most folks are just for convenience and will pay for convenience. I don't like to pay $5 a gallon for milk at Circle K, but what's my alternative? Drive several miles back into town to the grocery store to get it for $2.99 a gallon.

2) In the 'saving money' vein, why would the car makers put in a K&N filter and cut their dealers out of a lucrative tune up part. What's an OEM filter list for at a dealer? Motorcraft as well as AC/DELCO sell 'aftermarket' parts and air filters. As I noted, the owners manual for my Suzuki recommends Suzuki OEM filters (air and oil).

3) NAPA Gold oil filters (WIX) are noteworthy as being excellent filers. Why don't car makers use those?

You could say that Mercedes engines are very good; why don't all manufacturers use Mercedes engines. Your question really doesn't apply at all.


Cars used OIL BATH air cleaners for a long time, and when the time came the jump was made to paper filters when the technology was there. I just converted an early 60's Ford pickup from oil bath air cleaner to a paper cleaner. Much nicer.

Playing devil's advocate here...

If K&N filters are so great, then why aren't ANY OEMs using them?

 

[Philth]

I see your point, but why would they use paper in Corvettes, Vipers, etc?

 

[Top Gear]

Yea, I DO not have a 3.8 coupe (though I'd like to!).

They're awesome, I tell you

Are there any hard and fast dyno results on this? I know what the claims ARE; but its absolutely "interesting" that the simple removal of an activated charcoal element...

Well...that's the thing. At first, I was going by the troll's haven which is "jen coupe dot com" (sic, which we cannot utter or link to here). Reading through all the BS from their snake oil salesmen (site sponsors), I kinda picked up on this thinking from some guys who figured it out, and then I thought, hey, it won't cost me to try it! So, I did and that's that. I wish I could give you some figures, but if you do a search and read up over there you'll see the trick is very common, and is easily a 10hp bump or more, whereas just doing a K&N alone is essentially worthless, due to that extra filter. And speaking of worthless, the carbon filter only comes into play in rare situations when there's a slight spitback, which wouldn't happen if you don't run crappy gas, and even then it's not every time you turn off the engine. Sooo......

...Based on ONE filter a year, that puts me on the plus side.

I hear you (and I'm diggin' your sense of humor, Man). I'm on a "premium service plan" with the dealer, so the filters are free, in a sense, as I'm already paying for coverage. It's pretty cool knowing I can drive hard and get my jollies and then take it in on a regular maintenance schedule...or for other goodies, even. My last car was "paid for" - which means it had 250k on it when I parted with it - so it's nice to have that "luxury", hence not wanting to muck it up with a pesky K&N

 

[QuantumRift]

+10

they're awesome, i tell you

Well...that's the thing. At first, i was going by the troll's haven which is "jen coupe dot com" (sic, which we cannot utter or link to here). Reading through all the bs from their snake oil salesmen (site sponsors), i kinda picked up on this thinking from some guys who figured it out, and then i thought, hey, it won't cost me to try it! So, i did and that's that. I wish i could give you some figures, but if you do a search and read up over there you'll see the trick is very common, and is easily a 10hp bump or more, whereas just doing a k&n alone is essentially worthless, due to that extra filter. And speaking of worthless, the carbon filter only comes into play in rare situations when there's a slight spitback, which wouldn't happen if you don't run crappy gas, and even then it's not every time you turn off the engine. Sooo......

I hear you (and i'm diggin' your sense of humor, man). I'm on a "premium service plan" with the dealer, so the filters are free, in a sense, as i'm already paying for coverage. It's pretty cool knowing i can drive hard and get my jollies and then take it in on a regular maintenance schedule...or for other goodies, even. My last car was "paid for" - which means it had 250k on it when i parted with it - so it's nice to have that "luxury", hence not wanting to muck it up with a pesky k&n

 

[BlueGenny12]

I agree with most of your statement, however, I wouldnt go as far as saying manufacturers "super tune" their cars. My car runs pig rich, as evident by the black soot on my bumper and the black smoke that comes out at WOT. Its not a billowing plume of smoke, but its noticable. None the less, my car runs super rich.

Most stock cars come under tuned (rich) for efficiency. Any BPU mod is worthless on these cars without a pro tune map. And since our cars are not tunable, then its a waste of money. Just my opinion.

Sorry, but this is not necessarily accurate. The "black soot" is carbon leftovers from burning off the air and fuel. The soot doesn't necessarily distinguish rich or lean mixtures. In my opinion, even if they don't get you a ton of horsepower they DO help. The combustion in your engine accures in milliseconds. I would hardly say it's worthless that adding air to the engine could create a strongER combustion.