The world’s most radical road car, Ariel’s Atom has captured the imagination of petrolheads ever since it came to market in 2000.Its exoskeletal tubular chassis design guarantees a unique presence and a level of unparalleled driver feedback – and not solely through the helm, as an Atom's occupants are fully exposed to the elements.The first Atoms were powered by Rover's venerable 1.8-litre K-series engine but these days Honda’s K20 two-litre engine has become the mainstay of the Atom range.These highly tuned Honda K20 mills produce either 180kW in naturally aspirated form or 220kW with the benefit of belt-driven forced induction. The Ariel Atom's performance is, unsurprisingly, epic. At track-day events Atoms are regarded with respect and awe for their raw dynamics, unfettled by contemporary traction aids and stability intervention systems. Ariel even introduced a V8-powered model in 2010 for those Atom customers with a track death wish.10 YEARS ATOMIC PERFORMANCEWhereas the company's 2010 model line-up was dominated by the late introduction of the V8 (video), for 2011 the company is going commemorative. The latest Atom variant is a limited-edition model celebrating the relationship between the British niche manufacturer and Honda tuning specialist Mugen, and 10 years of Atom production. Lifting Honda’s K20Z-series engine from its legendary (and now defunct) Type R Integra, Mugen’s finessed it to produce a rather outlandish 198kW at a heady 8600rpm for Ariel's requirements. Not bad (at all) for a naturally aspirated two-litre four-cylinder engine. How did Mugen’s Northampton-based specialists achieve a near Touring Car racing output without the assistance of a turbo? Well, thanks to expertly blueprinted internals, the Atom 3 Mugen's engine is impeccably well balanced. There are plenty of trick components, too. The engine runs higher-compression pistons, rolls high-lift camshafts backed by custom-coiled valve springs and breathes through a more capacious free-flow inlet manifold, servicing larger diameter throttle bodies. RED, WHITE AND BLACK: Honda’s legendary motorsport colours run all over this Atom. Mugen badging leaves no doubt as to its performance potential. Transferring power to the rear differential is a six-speed Honda transmission. On a high-friction surface Ariel claims the Atom 3 Mugen should be good for a 0-100km/h sprint time of 2.9 seconds. Employ full power in sixth gear and a top speed of 250km/h is possible.You would have to be an unashamed masochist to sustain its peak velocity for more than a few seconds at most considering the Atom's lack of body panels and susceptibility to cockpit wind buffeting. The Atom 3 Mugen runs a similar double-wisbone configured adjustable damper and spring package as its heavier forced induction 300 series sibling. Distinguishing the Mugen model from other Atoms in the Ariel range is a classic Honda racing red, white and black colour scheme. Ariel will only produce 10 Atom 3 Mugens, one for each year the company’s signature track day machine has been in production. Befitting their limited edition status, these Mugen cars will be appropriately priced the equivalent of R550 000.