K&N cold air intake

[Vtur]

Why they called CAI when it's filtering engine compartment hot air. The stock setup appear more cold air to me with a front intake air duct.

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[ShadowsPapa]

Why they called CAI when it's filtering engine compartment hot air. The stock setup appear more cold air to me with a front intake air duct.

Yeah, it's a joke. I'm sure it's more of a marketing thing because if you are RACING, or needing every last half HP out of your rig, a true cold air intake system can help. These in their stock form, no hole or opening in the hood, it's a joke.

Some of us have actually done a cold air thing with our cars over the years and it involves pulling ambient air from OUTSIDE of the engine bay.
Even AMC in the 80s ran a duct up to between the headlights to channel cooler outside air into the air filter housing once the engine was warmed up.
Once the air is behind the grill or radiator, it's certainly no longer cold, not even cool depending on where it's taken from.

 

[@californiajeeping]

Why they called CAI when it's filtering engine compartment hot air. The stock setup appear more cold air to me with a front intake air duct.

there is no change in IAT or boost with this setup.
Obviously when a turbo is heating the air to 350-370 degrees……a 20 degree iat inlet change doesn’t matter.

 

[ParatusExpeditions]

Found this comparison on AFe' s website: https://afepower.com/air-filter-media
Feels a bit marketing-oriented but it's interesting that they don't rate their Dry media as well

 

[@californiajeeping]

Just an FYI: Checked my filter at 7000 miles. The KN has very very little visible dirt and is sitll most red/pink.

The prefilter was VERY VERY dirty. Muddy water came out of that thing when I washed it.

I had previously lightly oiled it and clearly its catching a ton of dirt and debris.

I am going to replace it with some UNI filter media that is oiled just for extra filtration but I think this KN system works great for a diesel.

 

[ShadowsPapa]

That's what pre-filters do - catch debris and larger dirt, leaving the small/fine stuff for the final filter.
A pre-filter is't to take the place of a filter, it's to catch the chunks so the chunks don't plug the filter.
Filters that are layered, have one or more "pre-filters" (thus the term - PRE - BEFORE the filter) have progressively finer or smaller "holes".
A pre-filter catches the bigger stuff - then the next filter in line catches the stuff that gets through the outer pre-filter, and then the final filter catches the small stuff.
Leave off the pre-filter and the filter has to catch everything, big and small and gets plugged up with the bigger bits, filling up faster.
The pre-filter isn't catching the fine stuff a normal filter is supposed to catch, otherwise, what's the point of a filter beyond the "pre-filter" ?

Sorry, but in the end, it's proven nothing except the pre-filters are catching the chunks. You have no idea what's gotten through and the K&N beyond the pre-filters has caught or not caught.

You could put a flour sifter in there in place of the K&N if your "pre-filters" are doing that great of a job. And if they are, they aren't exactly pre-filters.

From various automotive air filter sites->

Pre-filters are designed to keep out larger particles of street debris such as rubber, dirt and sand from getting into and clogging the pleats of air filter elements.
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Pre-filters are designed to keep large debris, such as mud clots out of your air filter. The openings on a pre-filter are much larger than the ones in your air filter, so it is the filter itself that protects your engine from dust. It is important to examine track conditions when deciding whether you will use a pre-filter as it can add a small level of restriction and reduce torque.
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All we know is that it caught a lot of dirt/dust. Do we know how much gets through?
It's the final filter that keeps the small stuff out - and there's no way to measure that in this case.

 

[BlueScapegoat]

Just an FYI: Checked my filter at 7000 miles. The KN has very very little visible dirt and is sitll most red/pink.

Exactly.

 

[@californiajeeping]

I will yet again argue against your point.

In my experience the oiled filter media will clearly visibly show dust and dirt during use.

Example my harley uses a similar media and is very dirty (PS its a KN filter). Upon teardown there is nothing to note dust/debris infiltrating and causing an issue.

An oiled foam filter is going to stop most of the particles that would damage the engine. The KN is also there to stop more.

None of my dirtbikes have ever had more than a oiled foam filter and have never had issues with dirt ruining an engine.

Im not arguing that a KN oiled filter is equal to a proper paper dry media filter but that in combination with a oiled foam pre filter it is adequate for this application.

Also when I changed my intercooler tubes 500 miles ago there was oil residue inside the tubes but not visible dirt/debris. If there was massive amounts of dust going past this setup it would have been obvious inside the oily tubes. The intake tube was clean this was from turbo to intercooler.

 

[@californiajeeping]

I’m at 15k miles.

the uni foam oiled works! No dust inside the intake pipes.

I clean it every 5k miles or after a off-road trip. Friends have had their stock filters clogged with dust after a day of fire roads and my Kn still looks clean?

 

[paclives777]

There is no change really. There isnt a power increase BUT when you first roll the throttle on prior to a downshift it spools up and hits full boost a bit quicker.

I imagine with a derringer it will be better. I am going to definitely look into pulling the CCV tube OUT of the intake stream a bit. It sticks WAY into this intake. Likely to prevent a CEL due to the larger diameter intake tube and less vaccum on the ccv?

Something to look into for sure.

I just got mine. That tube they send with the 45degree cut physically doesn’t fit in the tube. Did I get a defect or am I doing something wrong?

 

[@californiajeeping]

I just got mine. That tube they send with the 45degree cut physically doesn’t fit in the tube. Did I get a defect or am I doing something wrong?

That tube goes into the intake tube by the turbo with a grommet. A hose attaches to it from original ccv.

 

[paclives777]

Yeah. In the directions, it’s in the tube im
Holding it next to. Clearly not even close to fitting in there.

 

[paclives777]

That tube goes into the intake tube by the turbo with a grommet. A hose attaches to it from original ccv.

 

[Almost]

For those wondering just how bad K&N is here is some actual proof. It’s beyond bad.

Project Farm did a great test on this.

 

[@californiajeeping]

Honestly looks like you need to clean or ream the hole with a drill or send it back.

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