I've seen/assisted in a 1100whp EVO 9. You can do it, but it's expensive. Everyone thinks 1000 is easy and you just bolt stuff in. /ubbthreads/images/graemlins/rofl.gif
We had 30k in the build to hit 1100whp. 4 turbos, 12 pistons, 8 rods, 1 engine block, 1 cosworth mivec head, 3 exhausts, nitrous, multiple sets of cams, several clutches, etc. and that's the start. 100+ gallons of c16 fuel...
Not only do you break things, but the cost of swapping parts to try other ones to get more power, that's the bank breaker.
And that's just engine stuff, now with 1kwhp, you have to put it to the ground. 1kwhp builds are a joke in my opinion. Anyone that says they are shooting for that, I always tell them to call me in a year when they are parting everything out.
That reminded me about the MIVEC cam that exploded during a dyno pull.