It bums me out that the only filter K&N offered for my 2007 V6 that is California street legal is a drop-in. Lame.
So, I did some digging and I found this
https://www.knfilters.com/mobile/mPr...cid=ADDCABINAI

Interesting.....has anyone else tried using this? Looks like it will just plug right in and replace stock air train.

in the airbox yet? might save you that $313 with some of the same results

Observations after removing the hydrocarbon filter

HCF was deleted a year ago when I picked up the truck. And a k&n drop in replaced the paper filter. The issue here, is the restriction from the factory air intake tube and surface area of the drop in versus the cone shaped filter and smooth tubing in this kit. In my experience, the drop in filter never performs the same as a full intake kit. Proved it on a 99 Ranger and my 2004 corolla. Massive difference in throttle response, improved fuel economy.

Most on here...T4R.org, think these are snake oil.

Not sure about the one you posted but the series 63 is the one for our v6 4runners I believe. Have had one on for 5+ years.
https://www.knfilters.com/search/pro...x?prod=63-9023

Sadly they only really make the motor louder.
To get any real improvement you need to add the URD MAF.
just plug it in.
https://www.urdusa.com/urd-maf-senso...lay-version-1/

or a wired in version for $40 less (have to splice into the factory wiring)
https://www.urdusa.com/urd-maf-sensor-calibrator/

The K&N will not improve your MPG...it goes the other way.

To improve throttle response try this intake spacer.
Toyota Gen2 Products | eXtreme Truck Performance ? XTP IMS intake manifold spacers for Nissan, Toyota & Suzuki with 4.0 engines for performance gains!

[QUOTE=BackOff;2958994]Most on here...T4R.org, think these are snake oil.

Not sure about the one you posted but the series 63 is the one for our v6 4runners I believe. Have had one on for 5+ years.
https://www.knfilters.com/search/pro...x?prod=63-9023



This is not a street legal option for California. I will definitely look into rhe MAF and TB spacer. Thanks for the input.

you can try to use the afe brand intake, i like it since its the same as the trd version. also just need to change out every smog. couple of bolts really.

Not sure if I'd call it snake-oil exactly. But I wouldn't expect any real performance gains or losses from the K&N. The real restriction is the throttle body, the intake hose is similar in diameter to the throttle body opening (maybe a couple mm larger or smaller I haven't measured it in a long time), so volume isn't the issue here. I suppose you could argue turbulence from the resonators and the uneven surfaces of the intake tube, but I doubt it's significant enough on a stock engine.

As @BackOff stated, you'll need a modified MAF for real gains in performance. I'm not sold on K&N (or any oiled filter for that matter) or "performance" filter's claims regarding being cleaner than a stock filter nor that their tacky oil doesn't get into the intake (whether or not it causes issues is debatable).

~

As for the HFC mod? Eh, I have yet to see any scientific data to prove anything regarding that mod besides reducing escaping hydrocarbons from the intake side of the engine.

Post Note-

I don't know if the V6's do this, but I have started noticing that all the K&N cone-style filters on the Tundra/Sequoia 3UR-FE's whistle at minor throttle input.

I can confirm the cone shaped filters made my ranger whistle, my corolla too. My brother has one on his dinosaur 2001 f150 as well, it still whistles 240,000 miles later, it was one of the first mods he did to it.

That's nice, a tube with an air-filter and it is off-road only...how is it really any different that any other design? Dumb.
I guess that URD MAF is off-road only too...sorry, not much help from me.


Throttle body.
4th gen V-6 has a 65mm(63mm actual)
At some point they got a 70mm(68mm actual) URD has an adapter for it.
The V-8 has 76mm.

The V-6 intake manifold is 68mm.
The K&N tube(series 63) is 68mm.


I never noticed any whistling...what like Andy Griffith show?
...or any over oil issue.


Some one just posted a pic, the HCF actually stopped a mouse that was digging in deep, went through the stock air filter...K&N has a metal mesh...

Here is the 65mm next to the 70mm.

Attached Images

 

No worries, I appreciate all the input. And yes, CARB is pretty silly. Case in point: on my 2004 corolla, cold air intake is not street legal, but ram air is?! Ya, that's right. Shoving a whole bunch of air down your engine's throat is ok, but cold air BAAADDD!!! What is the point? Don't get it.

I wonder how big my throttle body is...

(From another dumb thread about "cold air" intakes)

I dyno tested my supercharged 3.4 tacoma with all the aftermarket "cold air intakes" manufactured at the time. This would be in 2009. The dyno results conclusively showed that literally EVERY SINGLE ONE caused the engine to lose between 5-8 horsepower and the K&N drop in filter caused the engine to lose 4 horsepower. This is all dyno proven and we completely removed the filter to be sure, which caused a loss of 2 horsepower. The factory filter provided the most power in all cases.

The design of the factory intake has nothing to do with the volumetric flow of air going into the engine and everything to do with maintaining consistency of the laminar flow of air across the mass air flow sensor to prevent erratic fuel corrections due to low pressure losses caused from turbulence.

I also herd on teh internetz dat da blue intakes make 15hp more than the red intakez dawg! And it hella matchez my spoilerz and fast and furious racing stripez!

@BackOff

I honestly haven't heard it on any 4Runners yet. But I just had 2 Tundras last week and one today that had K&N Filters and at about 10% throttle application (which on those 3UR-FE is basically coasting/non-aggressive driving) there's an annoying whistle/squeal that echos out of the filter itself. I am guessing the lack of resonance chambers and more uniform interior surface is echoing a natural whistle caused when the throttle body is at such low throttle angles and it exists out of the filter cone.

I only notice it on the 3UR-FE Tundra/Sequoias, it might be apparent on other engines; but more than likely no one notices it because you're rarely going to be at that low a throttle application on most other engines.

Like I said I only noticed it because a customer had installed a K&N and complained about it and we definitively were able to notice it out the filter and compared it to a similar Tundra. Ever since then I can tell if a Tundra/Sequoia has a K&N filter without ever popping the hood because of it. I imagine most guys either learn to live with it or just drive aggressively and rarely notice it; but you're just being lax/easy driving it's there most of the time cruising. Not a huge deal, but more an interesting quirk I noticed.

Ok, so after speaking with a friend of mine who runs the smog shop in town I learned the following:

For an AM component to be street legal in Comiefornia, it must have an Executive Order number (EO), and it must match the vehicle for which it is intended in the CARB database, which you can access on their website. So, for the rest of the v6 4th gens in the Golden State, I did some digging and felt like sharing my research.

https://rover.ebay.com/rover/0/0/0?m...2F372006591539 cold air intake


https://rover.ebay.com/rover/0/0/0?m...2F301813189609 MAF sensor upgrade

https://rover.ebay.com/rover/0/0/0?m...lk%2Fitm%2F182 throttle body spacer.

Based on everything I have read, the combination of all three would be required to see any benefit.

Thanks to all who offered input, hope this helps others in my situation. Gotta love California....

replacing the intake with a smooth surfaced piece of muffler pipe. Theree a thread around about that mod being done on a 4th gen but without any real conclusive data.

And youre right it did improve throttle response noticeably.

Found this interesting youtube link experiment on air filters:
YouTube