Meet the 704bhp McLaren MP4-12C

Hand over the keys to your McLaren MP4-12C and a large envelope containing $19,500 to Hennessey Performance, and you'll receive something quietly quick. Well, perhaps not that quiet.

No, this isn't a cut scene from upcoming videogame Grand Theft Auto V, but a modification that very fractionally turns up the power on McLaren's MP4-12C supercar.

Hennessey's technicians have managed to outwit the MP4's mighty brainpower to tweak the ECU and increase peak boost from 21psi to 23psi. The company has also fitted an ‘enhanced' air-to-water heat exchanger which cools quicker as the boost levels rocket.

Dig underneath the heat shields and you'll find a new Hennessey stainless steel exhaust system that we're told beefs up the sound from that fettled 3.8-litre twin-turbo V8, while there's also high flow air filters and aluminium serial-numbered Hennessey plaques for the engine bay and interior.

The raw stats are thus: power rises from 616bhp and 442lb ft of torque, to 704bhp and 538 torques. 0-60mph takes 2.8 seconds and it'll do the all-important quarter mile sprint in 10.3 seconds at 137mph. See? A little quicker.

John Hennessey tells us: "Both midrange power and torque are bumped, but the rear hair-on-fire ride begins from 4,000rpm to the 8,500rpm redline."

And the result? "I gave you an extremely fast car," says David, first customer of the tuned MP4-12C, "and was given back a starship with advanced trans-warp drive." This coming from a man who reportedly has owned a Ferrari 430 GT1 racer and a Porsche Carrera GT.

Vijay Pattni