The Lamborghini Canto was a prototype built by the italian automaker Lamborghini and designed by the automotive styling firm Carrozzeria Zagato as an exercise to study potential designs for the Diablo's replacement. Various versions of the Canto were shown to the then-president of Lamborghini but unfortunately, the project was canned and was not deemed suitable to wear the Lamborghini badge. The concept never entered into production.The proposed engine was a 6.0 liter, V-12 engine producing 640 horsepower. If it would have entered into production, the engine would have been slightly detuned to 610 horsepower. (wikipedia & conceptcarz.com)
1999 Lamborghini Canto Concept
(Photos from andoniscars.blogspot.ca, lambo.dk, autonewsworld.com & modelclub.cn)