It's not often that we run a picture of the back of a car at the top of a story, but in this case we think it's justified. This is the first Audi R8 GT that's been rebuilt to Stage 2R Twin Turbo specifications by Underground Racing of Charlotte, North Carolina, better known as the builders of what they claim are the world's fastest Lamborghinis.
That's not surprising, given that only 333 R8 GT's were made, many of which are, sadly, cocooned in nitrogen-filled plastic bags gathering scarcity value, while the few that are driven are painstakingly kept absolutely 'out-of-the-box' standard for the same reason.
Charlotte is, of course, the home of many Nascar racing teams and over the years a thriving local engineering industry has sprung up dedicated to providing just about anything you can dream up in terms of performance components.
This astonishing 5.2-litre V10 has two rear-mounted turbochargers, each pushing air through a specially-made intercooler into an intake machined from a solid block of aluminium alloy and anodised black. Ignition and fuelling are orchestrated by a JRR Plug and Play Motec ECU, with a specially-made Egear wiring loom.
MORE THAN 1330kW
All of which delivers a dyno-guaranteed 850kW, running on the 93-octane feline urine that passes for petrol in the United States - and more than 1330kW on 117-octane racing fuel! - measured at the wheels, compared to the as-issued R8 GT for which Audi quotes 412kW at the crankshaft.
Needless to say, the original paddle-shift transmission would tie itself up in knots like a pretzel if you asked it to handle more than three times the standard power output so the Stage 2R conversion includes special input and output shafts, six special gears, custom final-drive and a helix differential - each carved from a solid block of high-tensile steel.
SEAT TIME REQUIRED
Underground Racing hasn't released any performance figures, beyond saying that it should be able to spank a twin-turbo Gallardo once the owner has learned how to control a lightweight coupé that has roughly the same power output as a Second World War fighter aircraft.
Underground Racing's twin-turbo conversions for the Audi R8 V10 start at about $110 000 (R1.15 million), not including the price of the original R8, which you have to supply.