Anyone using K&N drop-in filter? Any noticeable lost in lowend power?
Has anyone noticed any dirt building up on the top side of the filter housing?

Thanks

 

How about F-Sport air filter?

 

I am using the K&N. I check the filter once a month. There are noticeable color change on the filtering side. The top where the air exits is still as it came. This is through about 3 month of daily use. I also checked the inside of the pipe leading to the throttle body and there is no noticeable residue (dirt/dust) inside.

There is no loss of power. I doubt just the drop in would affect any performance aspect.

I have the Typhoon kit which comes with a smooth intake pipe and I have added a secondary air duct to the air box so there is a noticeable change in the way the car responds under full throttle. I cannot say it is really faster but the revs rises a bit quicker than when it was stock. Especially after 3.5k rpms. Been to busy to conduct tests to tell if 1/4 trap or ET has a statistically significant change.

 

I wouldn't recommend the K&N drop-in filter. Speaking from experience and pain.

 

Agreed. MAF sensor problems may result with use of the K&N filter.

 

I'm currently looking into Lexus IS 350 drop-in F-Sport air filter for GS 350. It's reusable and dry filter. I believe the IS and GS uses the same OEM filter. I think someone told me that filter might be manufactured by Blitz. Anyone using this filter already?

 

Here is K&N drop-in filter dyno video:
This one is for Blitz/F-Sport filter:

 

I recently installed a drop-in K&N filter. No problems. I put one in every one of my cars.

However, before I installed it, I washed it and re-oiled only one side of the filter; the side that is farther away from the MAF sensor.

Also, I noticed that there is another carbon filter that is fixed into the plastic top half of the filter housing. That should provide another stage of protection for the MAF.

 

I know some of the 4th gen v8 4runner owners remove the carbon filter as a mod..... increase airflow I presume..

 

I remember reading in a thread somewhere that removing the carbon filter actually decreased power...

 

Just wanted to let you guys know that I ordered 2015 Lexus F-Sport air filter (reusable/dry filter) for IS 350 and it fits perfectly in 2015 GS. I also noticed that white charcoal filter on top of the air box and even if you are using K&N drop-in filter I don't think you will have any problem with the oil getting to airflow sensor.

I only got this filter because I was told it's made by Blitz and it produced more HP than K&N drop-in filter.

I can feel a little difference is power but that might be just my head.

One thing that I also noticed is my engine is making whining noise around 2-3k rpm. Not sure if this is related to the air filter.