It's been a long time since diesels were clanky, slow, smelly and noisy, but very few carmakers have gone down the route of making a diesel sports car or supercar.

To some that might seem strange--after all, diesel engines are certainly capable of delivering high power and torque figures. In other ways, it's not that odd--what millionaire supercar buyer is really bothered about fuel efficiency?

British sports car maker Trident has gone ahead and built one anyway, and its Iceni supercar is set to appear at the prestigious Salon Privé show in London, this September.

The Iceni Grand Tourer is a 6.6-liter, turbo-diesel supercar putting out 430 galloping horses and a huge 950 pounds-feet of torque.

Thanks to long gearing that lets the engine turn over at only 980rpm at 70mph--while still delivering 700 lbs ft of torque for quick acceleration--Trident is claiming a massive 57 mpg on the combined economy cycle.

Now as we're obliged to point out, that's a European fuel economy figure and as such, may be a little on the optimistic side. You'd still need an electric supercar to beat it on efficiency, and even then the electric car probably wouldn't manage 2,000 miles on a fill like the Iceni...

Top speed is a claimed 200mph and it'll accelerate to 60mph in only 3.7 seconds. More relevant to green-minded buyers is the car's ability to run not just on regular diesel, but also bio-diesel, palm oil and linseed oil.

It's not even that expensive, as supercars go. Okay, so a price tag of $119,000 will put it out of reach of most mere mortals, but for Porsche 911 money you'd be getting a car that both out-performs it and uses significantly less fuel...

And as if all that isn't enough? Well, we think it looks pretty stunning too, making it a true British sports car.

The Iceni will be on display at the 2012 Salon Privé, held at Syton Park in West London, England. The show runs from September 5-7.


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