The horsepower proliferation war between the world's hypercar elite looks set to explode again in the next 12 months when both Koenigsegg and Hennessy will debut new versions of their Agera R and Venom GT respectively, both with significantly enhanced performance.

Only Hennessy has officially released details to us at this stage (along with projections that its new Venom GT2 will have a top speed of 287 mph), but some very credible images and details have also emerged to confirm the existence of the outrageous Koenigsegg One:1.

Koenigsegg has been rumored to have been working on a high(er) performance version of the Agera R for some time, and the rumors gained solid foundation when Top Speed published an image (below) which seemingly shows printed documentation and images of the new car on the coffee table at a private presentation.

Top Speed obviously has some excellent connections with Christian Von Koenigsegg, because it has now produced more images of the new hypercar.

While no official weight has yet been stated for the new One:1, the Agera R (pictured with Christian Von Koenigsegg above) weighs in at 2,932 pounds, which means that if it were to be brought up to a one:1 ratio, it would have 1,329 horsepower to match it's weight in kilograms (1329kg).

Now the One:1, if we go on Cars UK's conversation with Christian Von Koenigsegg, is likely to be "slightly lighter than the Agera R", and that power will be "somewhere between 1250hp and 1350hp."

The Agera R (above) produces 1140hp, so how much the weight has gone down and the horsepower has gone up to achieve power-to-weight parity is not yet known.

The Cars UK report also states that the One:1 will cost US$2 million, and the limited production run of five cars is being aimed primarily (we're not sure if this means exclusively) at Chinese buyers. No production date has yet been set according to the report.

The Hennessy Venom GT2

More tangible and with even more exciting numbers than the Koenigsegg One:1 is the Lotus Exige-based Hennessy Venom GT2, a derivative of the Venom GT which already had what Gizmag's Jack Martin described as "the most spectacular set of numbers of any supercar: 1200 horsepower shoehorned into a mid-engined chassis that weighs just twelve hundred kilos (2,685 lbs)."

So in case you're not aware, the 2012 model 1200 bhp 1200 kg Hennessy Venom GT already has power-to-weight parity, and as Martin irreverently observed in the same article, makes the "267 mph 1888 kg Bugatti Veyron GT look obese." Whereas the Koenigsegg is still "early in its development", Hennessy has already produced and delivered ten such vehicles.

The current Venom GT weighs considerably less than the current "king of the road", the Bugatti Veyron Supersport, which owns the world speed record for production vehicles at 267mph. The Bugatti has less horsepower (1184 bhp), and is 50% heavier, tipping the scales at 1,888 kg (4,162 lbs). By comparison, the Venom GT2's 7.0L twin turbo V8 produces 1500 hp on E85 pump fuel, giving it 1.2 bhp per kilogram of kerb weight (2743 lbs) and a projected top speed of 287 mph.

The GT2 has a number of other features designed to make it more accessible than could be reasonably expected of what will possibly be the fastest car in the world when it is released, thanks to its power output (a claimed 1500 horses) and aerodynamic efficiency (aerodynamic improvements to the side mirrors, roof and front air-dam have lowered the Cd from 0.44 to 0.42).

For starters, the new double bubble roof shape means increased headroom for taller drivers and the price of the Venom GT2 will be considerably less than any of its direct competitors at US$1.25 million.

Production of the Venom GT2 will be limited to seven vehicles. Applications should be accompanied by a urine sample and a letter from the local vicar.

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