Shortly after installing my new Magnaflow true dual exhaust system (see the "Exhaust" forum) I installed an FIPK on my 2001 4.6 5-speed. What a difference! My friends who already have them told me that the most noticeable thing is better throttle response, and that's very true. The thing just leaps when you hit the gas! It also has that cool old "flip over the air cleaner cover" sound when you floor it. Took about two hours to install, including one phone call to K&N about the idle air bypass valve. They show one picture with it installed and another picture without it. The K&N guy told me that without it, I would probably get a whistling noise at idle. I tried it first without it (because that's the easier way) and voila, no whistle. I know that there's been some debate about hot underhood air vs. cool fender air, but so far I've had nothing but good luck and increased performance with this mod. Combined with my new exhaust system, it's like I have a hot rod now. Next I have to get rid of that noisy engine driven fan, and maybe get a chip. Later.

 

sounds like you are on your way. another good and half way cheap mod is Underdrive Pullyes. allot of people think that it helps out allot but some feel that it losses too much power to other items. i.e. a/c and alternator. I have not done this yet but will soon enough. Stick around this sight long enough an you can find allot of other HP improvemtns all around $200 a pop. With the chip there is a guy in the chip forum that is a suoerchip distirbutor that can customize one to your liking. hope you enjoy this web sight. I have alos found the www.fordtruckworld.com and www.f150.net are both really good places to get ideeas.

 

I've been thinking about the pulleys, but I'm at least going to wait until after my warranty is up. Same with the electric fans and chip. I am concerned about the alternator output with underdrive pulleys. I have a couple years to look into it. Me plenty happy for now.