I have a 04 f150.. 4.6
i added a K&N intake 77-series and afterwards could hear and feel the difference..
but now when i give it some gas ( meaning floor it) it kinda has a delay, as to before it just took off.
What is causing that?
I herd i needed a exhaust kit to let the more air going into the engine out faster..
Any ideas??

 

You need a pcm reprogram.Are you sure that problem wasnt always there?
Just call the dealer with your vin and ask them if you have the latest calibration on your computer.
I did mine when i first bought and it felt like a totally different truck.
Good luck