British sports car brand Trident is set to launch two new variants of its Iceni sports car--billed as the world's fastest and most fuel-efficient diesel sports cars.

The Iceni convertible, the fixed-roof Iceni Magna and the Iceni Venturer wagon use a 6.6-liter turbodiesel V-8 engine to deliver huge performance.

Despite this, Trident says the Iceni offers "outstanding fuel efficiency".

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It achieves this usually mutually-exclusive mix through the use of a six-speed automatic gearbox with "torque multiplier" technology.

Trident's press materials aren't clear on how this system works--though typical torque multiplication systems use an epicyclic gear set, to multiply gearing between input and output shafts in the transmission. 

The overall aim is to prioritize torque at low revs over top-end power and high engine speeds--much more useful in road driving.

It's not short of the power, developing 424 horsepower. But its torque figure of 950 lb-ft is very healthy indeed, and helps the Iceni to sprint to 60 mph in 3.7 seconds. Top speed is 190 mph.

The torque multiplier technology also enables a very low-revving engine, even by diesel standards.

According to Autocar, the gearbox changes up at just 3,000 rpm, keeping the engine in the thick of its torque band. At a 70 mph cruise, the engine turns over at 980 rpm--half that of most existing long-legged diesel vehicles.

The upshot is economy of 57 mpg at that speed--far greater than you'd expect, given the Iceni's huge engine. Thanks to an equally huge fuel tank, the Iceni also makes the perfect Grand Tourer, with a 2,000-mile tank range.

Further adding to Trident's green credentials, all three sports cars can be run on 100 percent biodiesel, if required.

As you'd expect from an upscale British sports car brand, the Iceni's interior is bedecked with leather and Alcantara trim, and offers typical features like DAB radio, air conditioning, a set of neatly-trimmed sports seats, and more.

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The car's low-volume nature means customers can choose their own specification requirements, for a more individual vehicle.

The final detail is the Iceni's price.

At £96,000--just over $161,000, at current exchange rates--it isn't cheap.

It is similarly priced to the new BMW i8 plug-in hybrid sports car however, with similar performance and potentially, better economy at a cruise.

And both cars are considerably thriftier than similarly-priced rivals. Are we entering a new age of low-consumption, low-emission sports cars?


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