Lotus Circuit Car
From Lotus press: The visually dramatic open-topped prototype “Circuit Car” has lightweight composite bodywork and a very powerful supercharged and intercooled 1.8 litre engine.
The innovative and technologically advanced extruded and bonded aluminium chassis has high side sills that reduce the complexity of the chassis structure.
The engine with VVTL-i (Variable Valve Timing and Lift – intelligent) is mated to a Roots-type Eaton M62 supercharger with air-to-air intercooler to give a maximum power output of 243 hp (181 kW) at 8000 rpm and a maximum torque of 174 lb ft (236 Nm) at 7000 rpm. On roduction versions, an entry-level naturally-aspirated VVTL-i engine will also be available with 190 hp (141 kW) at 8000 rpm and 138 lbft (181 Nm) at 7000 rpm. Engine management control is provided by the bespoke - mapped Lotus T4 system and a drive-by-wire electronic throttle.
The 6-speed C64 close ratio gearbox is linked to an open slip differential and a prototype traction control system perfect for the tight and twisty Shelsley Walsh Hill Climb course.
The power to weight ratio, of course a key Lotus engineering principle and core brand value, for the supercharged engine is around 373 hp/tonne (278 kW/tonne) with a torque to weight ratio of 267 lbft per tonne (363 Nm/tonne). It is estimated to achieve the 0 – 100 mph (160 km/h) sprint in less than 9.0 seconds. This exciting combination has allowed for a dynamic racing package producing higher performance to that of existing Elise-based products, powering the car from 0 – 62 mph (0 – 100 km/h) in under 4 seconds.
Braking is provided by a servo-assisted, track tuned 4-channel Antilock Braking System (ABS) with Lotus/AP-Racing twin-piston fixed aluminium alloy front brake calipers, Brembo single-piston sliding rear calipers and 282 mm diameter, 26 mm thick front and rear, cast-iron ventilated & cross-drilled discs.
The lightweight GRP composite bodywork is bolted to the chassis for easy removal for maintenance and race / track preparation. The bodywork has been designed by the Lotus Design team led by Russell Carr, Chief of Design for Lotus. Russell Carr, explains the design philosophy of the new Lotus “Circuit Car”: “The design captures the essence of the other Lotus based products and combines it with a functionally correct bodywork to give a racecar that is not only beautiful to look at but aerodynamically and structurally as effective as it possibly can be.”
The small frontal area with no windscreen is combined with flat, unsculptured sides with no airintakes, for minimal drag; and a deep front splitter and a large rear wing (single plane as standard and dual element as an option) and a rear diffuser to attain maximum aerodynamic downforce.