K&N air filters and air chargers

[thebitz1]

Either I am being stupid (been accused of this) or I am not searching for this correctly (probably the reason)

But I can't find any information on K&N filters here and I know I have seen posts before.

I have a 2003 Limited.
I have used a OEM K&N replacement before with decent results, but I am looking for information on K&N filters

1) good or bad for 4Runner?
2) comparison between OEM, 63 and 77 Series air chargers. (benefits of each) It actually looks like the 63 "get" more HP than the 77.
3) worth the price? my search yielded $49, $290, and $387
4) how much MPG gain have people seen on each??

 

[fullboogie]

My two cents - if you're looking at buying a K&N for performance or MPG, you're likely going to be disappointed. I bought the panel version for ease of cleaning and costs over the life of the truck. But you're not going to notice any difference in how the truck drives. At all.

 

[wnelax04sr5]

hopefully ill save you some time here

A. the general consensus is that more air in=less filtration
B. 4th gens by design already have a cold air intake, the air is pulled from the passenger side wheel well
C. the only improvement found with a cold air intake will be noise and air flow through the intake tube, the stock filter/air box design is decently restrictive due to the initial bend after the resonator into a wide filter then crammed back down into the TB.
D. I highly doubt you'd see any MPG gains with any of the options you have listed. the drop in filter really won't change too much, and the cold air intakes will make you put your foot in it way more often to hear the noise, which is intoxicating, i know because i have one.
E. power. the intakes claim to add power, but without a little tuning like the MAF Calibrator from URD, the computer won't take advantage of the increased flow of air coming from a cold air intake.

lastly, id stay away from oiled filters, they're easy to mess up and over oil, and under oiling them results in more particulate ending up in the engine. id also stay away from a cold air intake if you live in a particularly dusty area, or if you plan on fording water often

 

[telum01]

I'm personally not a fan of oiled air filters. You're exposing yourself to the risk of fouling your MAF sensor and gaining nothing in return compared to a good dry filter.

 

[thebitz1]

Thanks for the quick responses. I had the OEM in my 2006 and I thought I got a 5% boost in mpg.
I have seen other posts with about a 50/50 opinion on oil filters. I believe there is a dry, reusable filter out there (forget the name) that is an option.

 

[97BlackAckCL]

I got a used K&N filter on ebay, and have had it on both my 4runners (03 and08) I cleaned and reoiled before installing in my 08, but it wasn't even really needed. I've had a K&N cone filter on my car for 10 years. They're great filters, and as long as you don't over oil them, you won't have issues with your MAF. Combined with the HCF filter delete, you definitely get some added throttle response and MPG, at least I have

 

[peebee]

I agree with others here. I would stick with a dry filter. Toyota has already engineered our engines with relatively high power and efficiency. You're not going to make any noticeable difference by changing a filter.

 

[wnelax04sr5]

I got a used K&N filter on ebay, and have had it on both my 4runners (03 and08) I cleaned and reoiled before installing in my 08, but it wasn't even really needed. I've had a K&N cone filter on my car for 10 years. They're great filters, and as long as you don't over oil them, you won't have issues with your MAF. Combined with the HCF filter delete, you definitely get some added throttle response and MPG, at least I have

^This

i totally forgot to add this to my post OP, with the CAI or HCF delete/filter, you will notice a big difference in throttle response, its much improved

 

[DisguisedRope]

I believe there is a dry, reusable filter out there (forget the name) that is an option.

I run the AFE pro dry s. Seems to be the recommended dry filter.

 

[marc_l71]

I run K&N filters on all my vehicles. As long as you clean and oil properly( not heavy or barely) you will be fine. I have also heard the AFE is a good filter. there is another that i heard of, i believe it is called Volant or something like that. Everyone has likes and dislikes.

 

[woblik]

So, I know this subject has been beat to death as it is on all car forums, but I will be trading in my 12 Durango R/T next week for a 06 4runner sport v6. I've always been a fan of cai, especially afe. But I am moving from WV to Maryland and will become subject to emissions inspections. Has anybody in maryland had an issue with inspections while having an intake like the afe?

 

[MarkinWMich]

For the vast majority of stock engines, from most manufacturers, there is little restriction to air flow on the intake side. There have been many, many dyno tests that prove this. Even if you have a significantly modified engine, any tiny (less than 15%) gains are going to be at the upper end of the RPM range and you will not feel them. Therefore, if you are running a stock engine in a truck, which typically runs at low RPM, spending your hard-earned money on a cold-air intake and "high flow" filter will yield you nothing but a lighter wallet.

If you want to gain a serious "seat-of-the-pants" feel from your rig, then change your ring and pinion to a 4.30 - 4.88 (depending upon your tire size). It will run you around $1000 (give or take) to do the front and rear.

If you are looking for overall improvement in engine performance, then go to a reputable "speed shop" that has a Mustang Dyno that can do a full tune throughout the RPM range, steady state performance, clean up any "flat spots", improve emissions, etc. Put on a 2-stage chip with an "economy" mode and another for "performance". It will run you around $1000 (give or take).

 

[Hayden_]

I've got a cold air intake on my 07 and don't have anything bad to say about it performance wise. What I will say is that if you plan on off-roading either don't get one at all or get one with a box/cover type thing on it. In bama we have a lot of mud and I've gone ahead and bought two now one for road and one for offroad. You don't want dirt and mud getting in your engine etc. Honestly though if you combine it with a nice muffler or exhaust system it will sound great. If you're looking for performance it's not really worth the price, if you're looking for noise then it's great and can hear it entering the freeway and going up big hills and things like that. I get lots of complements on mine though

 

[wnelax04sr5]

For the vast majority of stock engines, from most manufacturers, there is little restriction to air flow on the intake side. There have been many, many dyno tests that prove this. Even if you have a significantly modified engine, any tiny (less than 15%) gains are going to be at the upper end of the RPM range and you will not feel them. Therefore, if you are running a stock engine in a truck, which typically runs at low RPM, spending your hard-earned money on a cold-air intake and "high flow" filter will yield you nothing but a lighter wallet.

If you want to gain a serious "seat-of-the-pants" feel from your rig, then change your ring and pinion to a 4.30 - 4.88 (depending upon your tire size). It will run you around $1000 (give or take) to do the front and rear.

If you are looking for overall improvement in engine performance, then go to a reputable "speed shop" that has a Mustang Dyno that can do a full tune throughout the RPM range, steady state performance, clean up any "flat spots", improve emissions, etc. Put on a 2-stage chip with an "economy" mode and another for "performance". It will run you around $1000 (give or take).

im not really seeing how a dyno test, a measurement of horsepower and torque throughout the RPM range would show that there is little intake restriction.

not disagreeing about the stock intakes entirely, but I'm not so sure about it

 

[MarkinWMich]

im not really seeing how a dyno test, a measurement of horsepower and torque throughout the RPM range would show that there is little intake restriction.

not disagreeing about the stock intakes entirely, but I'm not so sure about it

The whole point of using a less-restrictive intake and/or air filter is to get more air into the engine, right? If, indeed, the new parts do deliver more air into the engine, then the sensors are going to see a change in the air/fuel ratio towards a lean condition. In turn, the computer will quickly respond by increasing fuel delivery through the injectors to maintain the programmed air/fuel ratio. Under most conditions, more air + more fuel = more power. It will be seen on the dyno.

Typically, if a stock engine is going to have a restriction, either on the intake or exhaust side, it will be at high RPM, not at normal cruising speeds. So, even if there is a 10% power improvement at peak RPM, you are only looking at 23-24hp, and I guarantee you will not feel it. At the typical 1500-3000 RPM most stock engines cruise and accelerate at during an every day commute to work, you will not feel any change, and probably will not be measured on a dyno, either. Save your money for more significant mods.