Prodrive creates the P2 sports car

Prodrive has unveiled the P2, a unique two-seater sports car with some exciting credentials. The P2 uses a modified 344 bhp, 575 Nm, Subaru Impreza STi engine and all wheel drivetrain, which incorporates innovative ALS (Anti-Lag System) and ATD (Active Torque Dynamics). If you haven’t heard of Prodrive, it’s probably because you don’t read the fine print. The company has won more than 100 international rallies and six World Rally Championship titles for Subaru, the British Touring Car Championship five times (with BMW, Alfa Romeo and Ford) and is also involved in numerous other international racing series, including managing the BAR F1 team. Prodrive also consults and develops road cars, such as the NARO and Tango, and has developed numerous cars for the likes of Aston Martin, Ferrari, Ford, General Motors, Subaru, Range Rover et al and despite the obvious focus on performance, the P2 has all the comforts of a luxury car, with a six speaker stereo system, power assisted steering and electric windows. The company’s Motorsport involvement becomes obvious when viewing the specifications of the P2 though, as it weighs just 1100 kg and has a power to weight ratio of more than 350 bhp/tonne, reaches 100 km/h in under four seconds and tops out at 280 km/h. The jury is out on whether the P2 will be produced in quantity, but with an anticipated UKP40,000 price tag, we expect the queue would be quite lengthy for a car of such remarkable real-world ability.

The P2 was the idea of Prodrive chairman and chief executive, David Richards, who wanted to create something that used the skills of every part of the business and demonstrated the company’s capabilities. "What we created is P2, a unique two-seater sports car, which has gone from concept to reality in just nine months,” said Richards, adding “and which is the perfect manifestation of what happens when our inspirational ideas combine with our innovative approach."

The P2 is a fully working car featuring Prodrive’s latest technology and which has been entirely designed, engineered and built by the motorsport and automotive specialist at its operations at Banbury and Warwick in the UK.

ALS – Anti-Lag System

The two-litre flat-four engine is fitted with Prodrive’s ALS . This has been derived from the same system currently used on the Prodrive-designed Subaru World Rally Car, but modified for use on the road. ALS can keep the turbo on boost at low engine speeds, giving the car immediate throttle response and improved performance by using more of the engine’s 575 Nm of torque throughout the rev range.

In tests, it has been shown to double engine torque at low revs, enabling a test car to accelerate from 30 to 50 mph in the same time in third gear as it would without the system in second gear.

Turbo-charged engines tend to run with a rich fuel mixture and, as a result, some of this fuel remains unburnt and ends up in the exhaust. At low engine speeds, when turbo-lag is experienced, the anti-lag system can introduce ambient air into the red hot exhaust manifold causing this fuel to spontaneously combust. This increases the manifold pressure, spinning the turbo back onto boost. In the Subaru World Rally Car, this gives Petter Solberg instantaneous response throughout the Impreza’s rev range.

"Unfortunately, transferring the system to a road car was not as straightforward as it might seem," said Prodrive powertrain engineer, David Hemming. "In a World Rally Car, our drivers are either fully on or off the accelerator and not concerned about how smooth the power delivery is. For motorists this is definitely not the case and an unmodified system would provide an unacceptable driving experience."

Prodrive spent six months developing the system on an engine on a transient engine dynamometer at its Milton Keynes test facility. During this time engineers managed to achieve closed-loop control of the turbo boost and make it work in a road car application. The system is so refined that it can control the turbo speed to within one per cent at almost any engine revs.

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