Today we're going to modify our stock air box to increase air flow into it by at least 50%. This will also increase the amount of cold, dense air, and increase air velocity into your cold side piping. This is applicable to 2011-2014 F150s with the 3.5L ecoboost engine. The process is fairly simple. UPDATE: I added a second one underneath this one. My intake temperatures now range from the same as ambient outside air to a maximum of 5°F above that. Prior to this mod, I typically ran around 15-30° above outside air temperature. Fun fact: Ford realized the flaw of having a fenderwell air inlet and rerouted the air inlet to between the grill and the hood in the 2015 F150s. This resulted in roughly a 25HP gain with just this change. On to the mod: 1: Loosen the hose clamp from the intake tube to the air box 2: Undo the 3 airbox retaining clips and move the top of the airbox and filter out of the way 3: Remove the retaining screw for the rubber splash shield and move it out of the way 4: Fit the 1.25" pipe through the space between the radiator and frame supports against the air box to see where you need to drill 5: Drill a hole with your hole saw from the inside of the air box where you determined the pipe would go through. 6: Put the pipe in the hole and measure how much long it needs to be so it can clear the grill 7: Cut the pipe to the length you measured 8: Insert the pipe in the hole and use the RTV on the inside of the air box to create a seal 9: Reinstall the filter, top portion of the air box, and retaining clips. 10: Reattach the air intake hose to the air box and retighten the hose clamps Parts list: -2' of 1.25" PVC/ABS pipe -RTV silicone -Optional: A second section of pipe for 2 inlets Tools list: -1.75" hole saw -Drill -Utility knife -Flathead Screwdriver -Saw ... https://www.youtube.com/watch?v=Tqkfnsyko5g