Improved fuel economy, pulling...
Improved fuel economy, pulling power, and passing power check, check, and check. This kit really does deliver on what it promises.
One of the first modifications new truck owners do is throw an air intake on of some sort. While most air-intake kits on the market do roughly the same thing (help the engine breathe better), the boys and girls over at Advanced Flow Engineering, aFe for short, have gone above and beyond the call with their '04-'08 Ford F-150 5.4L V-8 Stage 2 Si Cold Air-Intake System. The F-150 Stage 2 Si intake kit features a one-piece molded air box, which utilizes the stock air inlet for maximum air induction and on top of that makes use of an additional air scoop for even more air flow to the filter. Also included with the Stage 2 Si kit is an aluminum air box cover to help keep your filter protected from the elements that might contaminate the filter, such as mud and water. Along with better air flow, 65 percent better over stock, the Stage 2 Si kit really wakes up the 5.4L V-8 engine by providing you with a claimed 23 hp and 25 lb-ft of torque. Any of those things alone would make for an improved intake kit, but put them all together and you've got a kit that is hard to beat.
After 5,000 miles of testing, we are happy to report that the aFe Stage 2 Si kit is working flawlessly. We can really feel the increase in power on our patented butt dyno, and if we can keep our feet off the throttle, which is hard with the new found power, we have found that the intake kit has gotten us a solid 1-mpg-better fuel economy, and with gas prices the way they are, we'll take all we can get!
 Installation of the Stage...  Installation of the Stage 2 Si kit is simple and straight forward. Upon opening the box, you will be greeted by detailed instructions, with pictures, and all the parts needed to complete the install. |  Four bolts and a couple hoses...  Four bolts and a couple hoses is all that holds the stock intake in place, with the stocker out of the way we are free to install the new aFe unit in its place. |  As you can see the new air...  As you can see the new air box fits perfectly in the front right corner of the engine bay, almost like Ford meant for it to be there. |
 One hour after opening the...  One hour after opening the box the install is complete and we're ready to enjoy our new found power and fuel economy. | | |