There's an old saying in Texas that if lots is good, more is better and too much is just about right.
Well, Texas-based Hennessey Performance seems to be taking that to heart, with its recently-announced upgrade kit for the McLaren MP4-12C, which is not exactly slow to start with.
The HPE600 twin-turbo kit includes upgraded ball-bearing turbos with external wastegates and blow-off valves, a bigger intercooler and upgraded air-intake system and a custom-built titanium exhaust system.
With suitably re-mapped engine calibration, John Hennessy quotes 597kW, compared to the factory's 447kW.
Which is too much for the standard transmission, so the kit also includes a beefed-up clutch and a gearbox oil-cooler, but Hennessey has no plans to modify the suspension or brakes; he reckons the factory systems are well up to the job, even with an extra 150kW on tap.
CARBON-FIBRE AERO KIT
Part of the deal is a carbon-fibre aero kit that includes a low-slung front splitter with a huge centre air intake and a bonnet extractor. Whatever you may think of the aesthetics - and we think they're very Texan - it's necessary because that's where the bigger intercooleE and the transmission cooler live.
With that proviso, Hennessey is willing to upgrade your MP4-12C, either with the whole package or with individual components. Optional extras include special Hennessey rims, Michelin Pilot Super Sport tyres, and custom interior upgrades finished in carbon fibre, alcantara and various grades of leather.
Price, as they say, on application.