For the truly insane: 1800-hp Mosler MT900S

The standard Mosler MT900S is a supercar by anyone's standards. It's got a sleek body made of carbon fiber, a 7.0-liter V8 with 550 horsepower, and can hit 60 mph in just over three seconds. But for one of Mosler's customers it just wasn't enough. The owner of this MT900S enlisted the help of Nelson Racing Engines in Chatsworth, CA to build the ultimate motor for his supercar: a twin-turbo 427ci V8 producing up to 1800 horsepower on race fuel and around 1100 horsepower using 91 octane. To help make the car more streetable, boost can be controlled every 100 rpm in each gear. The first few gears are limited to around 6-8 psi, while higher gears can take full boost -- over 30 psi!
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