To add to that. Most of the inherent advantages of a FPC vs. CPC were given up during development. I know you guys will probably shoot me over this, but it is almost a marketing gimmick.
When you look at what Ford could have offered in a conventional CPC for the $ they spent on developing the FPC, it looked mighty tasty.
That's not quite fully genuine.
Are the differences critical? No, you can make great power with a cross plane crank.
The biggest advantages are:
1) The firing order allows them to fully wring out performance from all 8 cylinders. With CPC and the inherent firing order and double up pulsing and localized issues, the engineers and tuners have to tune to the limiting cylinder. That means if 6 out of the 8 could handle more timing, they're missing out because they have to tune to the lowest performer for safety. This means that all things equal (same stroke and bore) a FPC engine will be able to put out slightly more performance because you're getting the most from all the rotating components.
1.b) The even firing order also helps scavenging and helps the motor breath better. You don't end up with a double pulse on each side, trying to stuff twice as much exhaust volume into the same tube. This can be and is resolved commonly with headers (adjusting the length of the primaries) to even out the pulse, but still.
2) The FPC is much lighter and "rev" happy. Does this translate into performance? Yes, but probably not for what most people EVER use it for. This isn't formula one where cars are doing laps and running WOT up and down the rpm range where hundreds of iterations at a fraction of a second equate to seconds in total race time. But it does rev better. In contrast, the lighter rotating components also are a bit of a negative for launching and drag racing where combined with the trans, it doesn't carry as much rotational momentum into the clutch engagement/launch. Basically, in order to bring the wood, it has to be screaming and grab, vs. a motor/trans with heavier components that can hit hard upon clutch release.
3) The sound. THAT is marketing, but it is by nearly any poll or opinion, BETTER sounding. I happen to think that Ford's newer "flat head" firing order sounds awful. Like garbage awful. There's less than I can count on my hand number of newer Coyote's that sound even okay. Most sound like dogshit to me. The old 302s were good, the 4V modular sounded magical, the newer Coyotes honestly sound like a poor man's build with a crappy Flowmaster exhaust. This is all opinion of course, but the growl of the Voodoo sounds exotic, refined, put together, precise with a bit of violence mixed in. The growl/whine of the newer Coyote sounds as refined as a fist fight in church.j
The numbers don't lie. The voodoo continues to make power almost all the way to factory redline. Even more when the intake and exhaust is opened up. Does it have drawbacks? Sure. Can you get to the same performance with a CPC. Yes, just add a little more volume.