I'm sorry guy's but I have to stop lurking and throw the BALONY flag here. Horsepower has been available since the 50's. And I've seen just as wicked throttle response from carburetors as anything. We just like to live in the land of pretend for some strange reason?
I was raised with a father that drag raced in the late 50's and early 60's. I've seen 289 ford's that you would not want to get behind. For the life of me I've never understood why we pretend that only this "new" crop of motor's is the only available horsepower around and or the only motors that can manage a torque curve? Our boat's run either 34 or 36 mph which is a consistent RPM piece of cake for a real motor. It's the RPM band that's the tricky part(and still is). I've seen and done either advancing the cam or retarding it to move the RPM band not a big deal. For a real motor to hold 3,000 RPM or more, c'mon piece of cake! You just probably wouldn't like to ski behind it for the same reason's Bruce and Gator mentioned above.
I'm just an average skier, due to I just cannot afford water time much anymore. My PB is only 2@35 not earth shattering. I weigh about 180lbs. In 06' or 07' I skied behind a Malibu with a 385hp Hammerhead motor with Perfect Pass. I was thinking that it would rip my arms off, the swim deck was pounding at idle but the pull felt just like the 340hp Monsoon of another friend of mine.
Gator nailed it, when it all comes down to it we do not want a "Dead on" pull. We want ZO to give us 12 different mapping options to cheat/feel the pull of the boat. Don't mis-understand me I want them as well, but horsepower and or torque has never been the problem.
I wish I could afford the water around here once again, and I with all of you want that old hand driver from years past as well, but at the end of the day we are not looking for a stronger motor, we want to manipulate the pull. oh yeah, and stay in tollerance. :)