My K&N conclusion

Z'sFJ · 05-12-2008, 01:21 AM

I have now had my K&N drop in filter for a little over 2 weeks. My first complete gas fill up with this filter was 19 miles to the gallon. All city driving. A Cyclone air prefilter was added half way though my experiement. I want the air getting to the filter to be as clean as possible. So, I am not sure at this time just how much the prefilter added to the mileage. Anyway, another benefit that I have noticed is that the overdrive holds much longer before dropping down a gear. Probably due to the fact that more air is going into the intake. Has anyone else noticed these things with their filter? Just thought that I would share my experiences.

Zane

toykilla · 05-12-2008, 01:35 AM

Quote:

Z'sFJ previously said:

I have now had my K&N drop in filter for a little over 2 weeks. My first complete gas fill up with this filter was 19 miles to the gallon. All city driving. A Cyclone air prefilter was added half way though my experiement. I want the air getting to the filter to be as clean as possible. So, I am not sure at this time just how much the prefilter added to the mileage. Anyway, another benefit that I have noticed is that the overdrive holds much longer before dropping down a gear. Probably due to the fact that more air is going into the intake. Has anyone else noticed these things with their filter? Just thought that I would share my experiences.

Zane

So what was the mileage before?

**slither** · 05-12-2008, 04:06 AM

I didn't really notice much of a difference in mine except for the fact that I had a little better air flow and a cleanable filter. You have to remember to clean it!

**puulboy** · 05-12-2008, 06:02 AM

Quote:

Z'sFJ previously said:

I have now had my K&N drop in filter for a little over 2 weeks. My first complete gas fill up with this filter was 19 miles to the gallon. All city driving. A Cyclone air prefilter was added half way though my experiement. I want the air getting to the filter to be as clean as possible. So, I am not sure at this time just how much the prefilter added to the mileage. Anyway, another benefit that I have noticed is that the overdrive holds much longer before dropping down a gear. Probably due to the fact that more air is going into the intake. Has anyone else noticed these things with their filter? Just thought that I would share my experiences.

Zane

I would be very careful in dusty conditions. I had a K&N drop in that I pulled after the second trail. There was all kinds of dirt in my intake. Of course I am in AZ. Our dust is really bad sometimes. I don't think they have good filtering ability in very dusty conditions.
thanks
Don

FullTimeStud · 05-12-2008, 07:10 AM

I have tracked my mileage since I bought my FJ. I didnt see any noticeable change in mileage when I put in the K&N.

Puulboy, did you have dirt in your intake before or after the air filter?

***uphill*** · 05-12-2008, 08:34 AM

Quote:

puulboy previously said:

I would be very careful in dusty conditions. I had a K&N drop in that I pulled after the second trail.

Me too. I no longer use the K & N. One secret to making that filter work is the grease you need to pack around the edges to insure a tight seal. Even with that, I dropped the K & N in the dumpster.

Brock · 05-12-2008, 12:08 PM

we used to have problems with the K&N in our Cummins Turbo Diesels as it would let fine dust past the filter. Never good to see gunk building up from excess oil and dust past the filter element before it goes into the turbo. So changed over to the AMSOIL without a problem. We also recommended anyone with a AFE cone filter run a pre-filter as they originally were not true CAI and were open on top with just heatshields between engine and intake.

I got about 1.5-1.75 difference with the AMSOIL alone from oem....but also could be attributed to breaking in vehicle as well.

**Mtbcoach** · 05-12-2008, 12:20 PM

Quote:

uphill previously said:

Me too. I no longer use the K & N. One secret to making that filter work is the grease you need to pack around the edges to insure a tight seal. Even with that, I dropped the K & N in the dumpster.

I agree with this as being a primary "flaw" in some of the design to the drop in filters. I have not seen the dust issue in my intake with the K&N but I don't drive in the high dust conditions some of you west coaster/AZ drivers suffer through...

Z'sFJ · 05-13-2008, 12:48 AM

To answer the first question. My mileage around town is between 17 and 18. So, slight improvement there. This last tank was 21.4. That consisted of highway, city, and offroad driving. Not too shabby!

I did read the thread about the MAFS going bad from oil and dust. That was going to make me get an AFE filter. However, I also read about how people on here are raving as to how well the Cyclone air prefilter works. Then I found a swinging deal on the K&N. Probably the big thing for me is that I do most of my wheeling alone. I shouldn't have to worry about a lot of dust being kicked up in front of me. I would like to think that I covered most of the areas. So, I will either have a problem with it or I won't.

Anyway, I guess I am noticing the power a touch more because I live at a much higher altitude than most of you. It is nice to feel the transmission holding the gear than listening to it drop a gear.

Thanks for the advice! I will definitely keep an eye on things.

Zane

**FJoel** · 05-13-2008, 01:35 AM

I have only owned a handful of K&N air filters, but I too noticed that they flow REALLY well, but don't filter like I would expect.

I am very impressed with my aFe filters so far.