Off the shelf extreme speed just costs money now, as opposed to a few years ago. To go fast in the past, glow was the only option and a custom airframe. I was deep into the fast stuff beginning in the 80's. I currently fly an Enigma hotliner that resembles the X Plane except bigger. These things are very slick and easy to go fast. Mine weighs about 74 oz. w/ wing loading of a bit over 25 oz/ sq ft. It has a Neu 1512/ 1.5D/6.7 to 1 gearbox and swings a 18X22 GM folder, 5 cell 4200 Genesis battery, pushing 250 amps and 4000 watts. It can be launched flat footed and accelerates through 150 mph in about 3 seconds if held level and climbs vertical at about 120 mph from launch. The acceleration is just silly! Once flying you only need 2-3 second power burst (throttle on switch, crow on stick). Terminal dives (power off) are good for about 150+ and was radared at 172 mph from a level 2 second power burst. Power dives are not recommended as I fluttered the tail and was doing over 200 on pull out. That prop really unloads. The howl the prop makes when stalled is a bit startling but quiets down once doing over about 80-90. The scream the airframe makes as it cuts through the air is eerie and can be heard a long distance away. The slap of the prop when I switch off the throttle has gotten comments that I had broke something. My little Sunracer 1M pylon "only" does about 160 but seems like it is doing 300 due to its size. Again, if you want speed, without the mess and noise and goo, go electric. Beware, a 4.75x4.75 prop @ 30,000+ rpm makes a lot of noise. It is much easier but a bit more expensive. If you want to design, go glow or electric and have at it. I loved designing, but I have no time for it. My hotliner cost about $1600 and pylon types are much cheaper, but keep in mind that the smaller planes at those speeds disappear fast. I would MUCH rather
fly my hotliner than my pylon stuff any day.
http://vimeo.com/12902067
This is only about 400watts in this Sunracer
http://www.youtube.com/watch?v=xrYq-0qVeO8