Here's where the PCV Connects. No mods necessary.

 

Maybe i saw something I didn't........Do you have two tubes into your airbox? If so, you need a K&N RF1012............It comes with twin outlets and the PCV Line inlet built into the filter. This is my 4.9.

 

Anyone stating they can feel the difference is either lying or wishful thinking. With no other modifications even K&N claims only around 10 HP. There is no way you can feel a 10 HP difference at 5000 rpm in 5000 lbs of truck. It's more a long term thing.
Some new soup for discussion that fits here. Working on an alignment in the shop today we had some spare time while running a 2008 f150 on a Ford diagnostic system. We popped open the factory air intake ( similar to ours with a front feed ). The computer responded immediately even with the hood open. The maf noted increased air flow, the IAT registerd a temp increase. A few seconds later the short term fuel trim demanded a small raise in the injector pulse width. Granted this is a much newer, quicker system with more control but the functions are similar. It seems the air temperature had little to do with fuel command because it was within a range. However the increase in air flow from removing a very old dirty air filter was enough to demand more fuel. If I get a chance I would like to try more experiments with higher rpm and loads, but schedule at school is pretty tight. If I can ill pass on what I find. But based on this test it would seem regardless of temperature, reducing restriction will actually use more fuel at idle. If the numbers follow the trend this means more air and fuel throughout the rpm range. Which means more power, fuel economy should then depend on your right foot.
Of course note this doesn't account for air speed or wind chill effect. The engine will produce more heat at speed same the increased air flow in the engine bay will remove more heat. Higher air pressure at the outside intake should force more air in at higher speed. So things get more complicated. My original post was based on text book information so I tend to follow that. One thing my experiment showed me was how easy it is for engineers to get this information today. Built in sensors on a dyno in a wind tunnel can simulate road conditions pretty well so if they say it works I'm inclined to believe.

 

The butt dyno is much more accurate.

 

I will say I only noticed differences in throttle response on my truck because I was used to it being a dog. When I bought it was on 35's with 3.55's after adding my kit my economy picked up because I used less pedal for the same speeds I was before the kit. As far as feeling power at high end,my truck feels exactly like it did a turd. I can go as far as to say the same with my 240 I added a typhoon kit 10hp guaranteed, I felt no difference until I converted to solid engine and trans mounts. The only mod I've really felt and noticed giving more power in the rpm band is my exhaust kit. I went from hitting 80 in third at around 6500 rpm to closer to 4800-5000 rpm with the combination of mods.

 

I did so much maintenance at one time that I can not prove one thing was the best gain, except for the e-fans, but the freeer flowing intake using more fuel at idle is different, but makes sense. I had to adjust my idle down by a couple hundred rpm after adding the K&N but didn't associate it with the filter. A choked intake breathes easier minus the restrictions. More air, more fuel. I can say for a fact that throttle response was improved with the k&n......or was it the cleaning of the throttle body, or maybe the spark plugs or so on and so on. I can say, overall, nothing hurt performance. I had the great idea of adding the intake temp gauge and did learn just how cool under hood temps really are and that the difference between cai and wai really aren't enough to make a difference for the daily driver. I love to do the mods and the fact that I've learned with no errors is amazing for myself. Lol

 

I think that's how it usually goes. We get a filter kit, toss out a clogged paper filter, clean the intake, new plugs and wires, set the timing and if course it feels new again. I guess the lesson is just take care of your ride.