Two times 540 horses have been let loose by the house of Roush. The 2010 ROUSH Stage 3 Mustang and the 2010 ROUSH 540RH may share a powerplant and some other parts but they are not twins.

ROUSH Performance's HQ in Michigan is ideal for the kind of work the tuner does. Making really powerful and fast Mustangs is part of that work and this time not just one but two of these iconic Detroit ponies got roushed-up.

The first is the 2010 ROUSH Stage 3 Mustang which rides on 18-inch or 20-inch chrome. It comes with four-piston front brakes, a resonator exhaust, a ROUSH suspension system and a new upper billet front grille with no foglights.

Its power comes from a heavily modified 4.6-litre Ford engine with among others, forged aluminum pistons, new fuel rails, an upgraded fuel pump and a next-generation custom supercharger. The engine then ends up making 397kW (540hp). About performance; not much is being said except that ROUSH engineers recorded an 11.8 second quarter mile while testing at the Milan Dragway in Michigan.

Interior luxuries include a short throw shifter with a black or white ball, four-piece performance pedals and ROUSH leather seats embroidered with the legendary Jack Roush's signature. Only 103 units will be made and sold at US$59,945 (€40,700) suggested retail price each.

The second car, called the 2010 ROUSH 540RH (or the Hammer), has the same engine, manual transmission and power figures. But it also adds things like front and rear stabilizer bars and jounce bumpers, a ROUSH rear decklid spoiler and a revised suspension package.

"The new ROUSH 540RH is really intended to be a ‘sleeper' car," founder Jack Roush said. "It will be purposely built with minimal content as it was designed for the buyer who wanted the ROUSH horsepower but with a blank canvas that can be customized into their own personal one-of-a-kind ride."

Suggested retail pricing for the Hammer is US$46,145 (€31,300).

Roush Unleash Two 540hp Mustangs into the Community