Please excuse my ignorance, but are they worth the money? I'm looking at the K&N 77 Series for my 05 FX4.

 

Some would say yes, but for my truck, the $277 does not seem to justify the modest hp increase, not to mention resetting the computer to keep the lean codes off. But that is my opinion, I am sure there will be many that say "go for it!"

 

On my 4.6 K&N claimed 7 HP. Since the wife got it for me for Christmas and she works at a parts store so it wasnt full cost I did not mind putting it on.It actually gained 13 peak HP and I could tell a diffrence in the throttle response. What other mod can you do to gain 13 HP for 280.00? The tuner gained 10 HP if memory serves and the exhaust gained 19. So for 1k I got 42 hp. That is not bad

 

Get yourself a 3" Air Force 1 CAI instead of the K&N. I definitely think that a CAI is worth it simply from the increased throttle response you'll see. I remember installing mine and taking the truck for it's first ride afterwards, man was I impressed.

 

Thanks for the responses. Can anyone tell me how the K&N differs from the Air Force 1 CAI?

 

The Volant is serving me well. After a few tankfuls I'm now averaging about 13.86 mpg...up from 12.65. I'll gladly take a 1.2mpg bump.

 

Is resetting the computer a big ordeal? Also, what exactly are lean codes?

 

When I first asked the dealer they said just disconnect the negative battery terminal for about an hour. So I did that and 2 weeks later I was getting not reading readings at DMV inspection. So I went back to the dealer and they told me that the method I used doesn't completely reset the computer. So they flashed it and supposedly uloaded the latest software.

Here's the rub either way. It takes driving 150 miles where the ambient temperature is over 37 degrees F to go through the complete start-up/boot process. So if it's cold where you are, you may as well wait til spring.

Lean codes means too much air or not enough fuel...ie. the truck is running too lean.

 

Has anyone tried an air raid jr on their 5.4l 3v? It's a swap of the air intake tube and still uses the drop in filter. I thought about getting one for my 04.

 

So I ended up getting the K&N 57 Series vice the 77 Series. Bought it last week while it was on sale from: http://www.autopartswarehouse.com/.
Paid $238 no tax or delivery fee. Pretty good huh?

HarmsWay,
Thanks for the heads up. It's still pretty cool here. So, I guess I'll wait a while to install it.