Just got an 04 F150 Supercab 5.4L V8. I'm considering a K&N Intake and possibly a new muffler and/or exhaust. I'm definately not a mechanic by any stretch, and have a few general questions:

1. Does replacing the intake or muffler/exhaust have any effect on factory warranties?

2. If i were to get a K&N Cold Air Intake (FIPK) would i need to do any upgrades to the stock exhaust system?

3. I've done a little looking into mufflers and like the Flowmaster 40 (original). Would this tie into the stock pipes? I may down the road look into a dual exhaust, but for now, would just the muffler be a good first step?

Thanks for your help!!