The story of the Hellcat all began in 2011 when Chris Cowland presented the Hellcat project to the FCA product forum which included Sergio Marchionne and 20 other head executives.Cowland also asked and got approval for a 600hp engine that would put their rival to shame which was the Shelby GT500.Cowlands team successfully completed their goal in designing the 600 hp HEMI-based engine but they heard that Ford’s engine packed 600+ horsepower so Cowland asked the directors if he could cranck up the power up to 675 hp and they gave him the “GO” but only if he could develop the engine in the time given and with the same fuel economy goals.In fact Cowlands goal was always to get the engine up to 700 horses and the only concern was the time his team had to develop the engine.This crazy power remained a secret to almost everybody in other words e said:

Even some parts of the product development team didn’t know the powertrain team was working on a 707-hp engine. The horsepower tests were verified by the Society of Automotive Engineers – the gold standard of engine certification – but the numbers were never released within the company. It was Fiat Chrysler’s Manhattan Project, so secret that people working on one part didn’t know what those working on another were doing.
They were building an engine that would put to shame even an 640 hp V10 Viper.When Cowland got asked why he build a 707 hp Hemi he simply replied: “Because we can”