Need to replace the air filter on my 03 TL-S, and was looking at k&Ns. My question is this: does it make a big difference on these cars?

I have the stock airbox right now, and plan to put an intake on it eventually. I don't want to spend $50+ on an air filter that i will eventually be getting rid of if the difference is not really noticeable.

 

its fairly noticeable. do you have the intake resonator removed also? that'll free up some more air flow/power.

 

some more answers/opinions to your question:
https://acurazine.com/forums/search....archid=3659500

 

answer is yes. it will make a difference, it did for me at least. i had a really dirty air filter that my last previous owner did not change. changed it out with a k&n drop in filter and walah.. i felt more throttle response.

recently, i put back my cold air intake since no one wants to buy it :P

 

If you are going to do the K+N,definitly remove the lower air box.
It will help on the performace and will give a better sound too.
And to be honest you would not feel much of a diffence between the K+N and the resonator removed vs. a CAI.
The only reason I switched to a CAI was because I wanted to run a zex ejector air filter,well,and the look.But thats it.

 

gotcha thanks guys. K&N is ordered.

 

I put in the k&n and drilled 2 1-inch holes on the bottom side of the airbox along the wheel well side. Great throttle response and just a bit of intake drone -especially when the v-tec kicks in!. Easy to fill in the holes with one inch plastic plugs from the hardware store.
No loss of bottom end like a CAI and still good up top on a stock motor.

 

I had a K&N and intake resonator delete for a while and then got an AEM CAI years ago. There is a difference with the CAI but it's minimal. The CAI does sound a lot nicer though.

 

I've got a 2003 TL type S with the k&n drop in and the intake resonator removed, sounds great but the idle noise is a little annoying. I'm thinking cutting out the bottom of the air box will eliminate the humming, any ideas??? NooB here...

 

did you grab the small plastic piece when removing res box-it connects the 2 holes in bottem of airbox

I would not remove the entire bottem of the airbox, but ok to enlarge 2 existing holes or add a few more with the hole saw--the engine gets all the actual air it wants but more freedom wont hurt
Watch out for cutting debris and remove all--anything sucked inside the engine is disaster!!

my 01 has fake foglight holes, cut the driver side open to provide real outside air into the inner fenderwell- the new `air storage` area,,cubic feet instead of cubic inches of air available
makes a differance when on the throttle hard for ~lengthy amounts of time~

next thing to change is a heat blocking spacer for the intake manifold
OutlawEngineering or P2R are the choices for makers

 

My intake likes to hiss in the morning when its cold out.
Keep in mind an intake adds noise if you ever go for it...
In fog or moist air, the car doesn't quite have as much pep as dry air.

 

I took my stock air box and made a poor made cold air box cut the whole bottem out sounds good

 

When I put in the drop in K&N, I did not notice any difference - I got it so I could just clean it every so often without replacing it. I've done it on several cars now and never noticed any difference.

Eventually, I put on a Comptech Icebox omn my 03 TL-S, and THEN I noticed a difference. I put a K&NCone filter on it, once again so I only have to clean it...much better than the foam one that came with the icebox...