Here´s what i did about the k&a filter. i just took the bloody thing "the air intake in the fenders" out, it took me 2 minutes. I need higher air intake cause of many deep rivers we cross, my Q is.. i have seen some guys cut out half of the black plastic thing so the airintake is bigger than the filter, ...
IS THAT BETTER"
and what is the diff between my silly mod and the firp k&n kit.
Please look at the pic to understand ... Thanks guys ..
seeja Röggi.

 

Roggi
I've heard that the FIPK makes a big difference because in your current elbow there is a big restriction (Silencer). In warmer areas you will notice a loss of power with the filter open because of the under hood temps. I've noticed that already here on 90 and hotter days.

Here is my conversion. I haven't taken out my elbow yet but thats next.

 

I took my silencer out with a dremel tool. It's not that hard to do and it opens up the intake so it is much larger than a FIPK style intake.

The silencer is inside the plastic ( 90 degree ) fat tube w/ lines on top that mounts onto the engine throttle body. Its inside that, take it off and you see a smooth tube inside, carefully remove the tube with out damage the exterior body.

 

Here in Texas(105 degrees), this mod will get you better mileage but you lose power because of the density of the air..a relocation system or opening the wheelwell is probably better then just opening it to the heat under the hood..It does need something over the stock snorkel and 90 degree turn....

 

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i can not find the silencer or a tube can it be different in a 99 model 4,6L

 

Hey there
Your mod is pretty common, but keep in mind that the most restrictive part of the system is the tube. K+N's FIPK is carefully flow-tested for power. Remember, bigger is not better here. If you go with a diameter too big, you'll lower the intake air's velocity, and bog down at low RPM's. Also, you'll see that both the stock and K+N tubes are different diameters at different places on the tube. This is for flow reasons. Taking out the silencer tube has given some proven gains, but not on the whole power band. I tried it, and thern went to the FIPK - There is no comparison in the part-throttle feel! The FIPK is a great kit.

 

Here you go Roggi
http://www.fordf150.net/howto/airintake.htm

 

Here is a dumb question. I just bought a K&N filter and I'm wondering if I'm supposed to reinstall the black cover over the filter or leave it off as I see in some pictures.

 

See the Airbox mod in the Technical Articles section of this web site.

 

If you want to expose the filter. You need to cut off the lip nearest to the clamp. If you don't want it exposed just put the filter inplace of the factory one.