Which don't add up to anywhere NEAR 650 RWHP.
For that kind of number on a stock block 4.6, you're talking at the very least a heavy nitrous system, along with fire ringed pistons, low comp pistons, bored valves/heads, and a serious intercooler.
You might get it at the flywheel, but for RW you'll need race fuel. It's not gonna happen, but trust me, you will not notice the difference between a theoretical 650 and 500-550 RWHP in a daily driver. Even at the track, that is gonna be tenths with the same driver in similar cars.
And before the interrogation starts, I own an 03 Cobra with similar mods, as well as an 05 GT with similar mods. And no, I will not post photos as the cars are very unique and noticiable to thieves, ect.
And yes, I worked for only portions of the two. Wealthy family. Not my fault, but I wouldn't have it any other way.