just want to know what u guys have in your truck or if u can just give some advice. u know gain in horsepower if any. u know stuff like that so thanks in advance for n e help!!

 

I recently installed the KNCAI. Couple that with duel Maganflow pipes out the back you can def see a noticeable gain in HP, may 10% compared to stock (at least that's what the specs say) Either way I can def feel a diff in power. This on an 08 FX4. WELL worth the money and prob the most important mod in addition to rims / tires.

 

Well, im a total K&N dude. I installed a K&N 77 Series on my 5.4L I loved the sound that the aftermarket tube gave off, the little fuel mileage gain I received, and the overall power I got. Now given I never dynoed the truck or anything after I got it, the little power gain I felt was enough to make me a believer. Im guessing I might have gotten about a 2 MPG gain. At least thats what my averages said, compared to the stock filter system. I also love their filters. Very free flowing. Now it says you can wash them and reuse them. True, but I wouldn't wash it more than 3 times before tossing it. I noticed that about after the 4th time of washing the filter, it was letting more and more particles in all the time. I freaked out for a bit, but just got a new filter. But overall I love K&N. <3

 

S&B or AF1 are very good choices for these trucks. You won't get the full benefit of a CAI unless you have an exhaust and custom tuning.

 

Love my s+b great fit,looks,and performance.

 

what do you mean by "custom tune" as in a programmer? I just put a series 77 K&N on my 04 5.4 and have been using a hypertech power programmer running the "hi-performance" tune and have been running 93-octane for a year now.