Hennessey has given the Ford Mustang 1,220PS

It’s the latest engine transplant from Hennessey, the Texas tuning outfit which, when not busy with its own F5 Venom and 300mph record attempts, turns out re-engineered muscle cars and SUVs with unlikely amounts of power. The company has built more than 12,000 re-engineered vehicles in the past 30 years.

Some have had more power than this latest effort but it is doubtful any have offered more bang for your buck. The Hennessey Venom 1200 Mustang GT500 will set you back the equivalent of £52,000, on top of the cost (from around $80,000 in the US) of the Mustang Shelby GT500 on which the conversion is based.

The GT500 is enough car for most people – with 770PS (574kW) and 847Nm (625lb ft) of torque it’s the most powerful stock ‘Stang ever. It’s not enough for John Hennessey and his tuning shop though.

Using tried and tested hardware – a bigger supercharger, high-flow induction system, new fuel rails and injectors, upgraded lines, belts, and tensioners – Hennessey has squeezed 58 per cent more power from the hand-built supercharged 5.2-litre V8.

The result is a dyno-confirmed 1,220PS with 1,223Nm (902lb ft) of torque. The dual-clutch transmission is recalibrated to cope, but the car remains rear-drive only, so getting off the line without melting the tyres is likely to require a deft touch. 0-62? Nothing official, but the standard GT500 is already credited with 0-62mph in 3.5 seconds. Will the Hennessey version by quicker? Ask the tyre engineers.

“The stock Shelby GT500 is an extraordinary muscle car,” John Hennessey tells us. “But we take it to the nth degree. Only a handful of vehicles in the world offer this level of power… especially at this price point.” 

US price for the conversion is $59,950 plus $4,950 for the red, white and black livery famous from the Ford GT40 MkII that ran in the 1966 Daytona 24 hours. The Texan firm says it will make only 66 of the ultimate Mustang muscle cars, all numbered, and that they will be available “for international shipping now through authorized Ford retailers”. Like all Hennessey machines it comes with a warranty.

Will the first person to bring one into the UK please bring it to Goodwood – we want to see just how much tyre smoke it will make going our Hill.