[4][5] The name CCX is an abbreviation for Competition Coupé X, the X commemorating the 10th anniversary (X being the Roman numeral for ten) of the completion and test drive of the first CC prototype in 1996.

[6] The CCX was unveiled at the 2006 Geneva Motor Show, sporting body modifications to meet US vehicle regulations and a new in-house developed 4.7L twin supercharged V8 engine capable of generating a maximum power output of 817 PS (601 kW; 806 hp) at 7,000 rpm and 920 N⋅m (679 lb⋅ft) of torque at 5,500 rpm while running on 91 octane gasoline.

The new engine is of all-aluminium construction made out of 356 aluminium with a T7 heat treatment to further enhance block integrity and cylinder bore chill during casting.

[5] The engine is lubricated with a dry sump system with a separate oil pump and the pistons are cooled by means of an internal cooler that sprays oil onto them in order to run high cylinder pressure with 91 octane fuel making it capable of 14 mpg‑US (17 L/100 km; 17 mpg‑imp) in combined cycle and 18 mpg‑US (13 L/100 km; 22 mpg‑imp) in highway travel.

[5][8] The CCXR is a more "environmentally friendly" version of the CCX, powered by the same engine, but converted to use E85 and E100 ethanol fuel, as well as standard 98 octane petrol.

The Edition models are more track oriented compared to the standard models, being equipped with stiffer springs and anti-roll bars, new dampers and a lowered chassis, a bare carbon body, unique 11-spoke aluminium wheels with a unique rear wing, and a larger front splitter and side winglets, all of which make the car capable of producing 350 kg (772 lb) of downforce at 250 km/h (155 mph).

All other extra equipment for the Koenigsegg CCX and CCXR Edition comes as standard which include optional carbon fibre wheels, a rearview camera, Satnav or Bluetooth, amplifiers, and an exhaust system made entirely from inconel.

Later, Koenigsegg also built two CCXR Special Edition cars which when compared to the old CCXR Edition had equipped with the double F1 wing, a revised aero package with a unique and larger front splitter and side winglets, wheel vents on top of the body, as well as Koenigsegg's first F1 Paddleshift system.

[25] The CCGT's engine is based on the unit used in the Koenigsegg CCX with the superchargers removed and the capacity increased to 5.0 L to compensate for the loss of power.

[31] The car originally lapped the circuit in 1:20.4, but was then fitted with an optional rear wing to provide downforce after The Stig spun it off the track at 130 mph due to a power steering failure.

The Stig purportedly recommended this modification, predicting that the car would then be the fastest ever round Top Gear's track[32] but Koenigsegg later stated that the improvement was due to adjustments to the chassis and suspension settings and not the addition of the rear spoiler.