Better known as a bio-fuel favored by Iowan farmers; Ethanol, or E85 in this case, has a higher octane rating (typically 100-105) than traditional pump gas, which allows higher compression ratios and more power. The engine actually makes only 350 HP in its current form, with the 150 necessary to take that figure up to 500 HP coming soon in the form of a turbocharger.
There's no fancy traction or stability control keeping all that power in check, so it's all going to be up to the rider being careful with the throttle and quick with the countersteering. Luckily, the rear track is much narrower than the front, which should work to counteract a quad's naturally tendency to dump riders on their heads, encouraging rear slide over grip. [via Hell For Leather]