Article
Articles, Issue 45 - Summer 2012

Raw Performance

The Exige represents the very essence of Lotus – raw performance, agility, unparalleled ride and handling and mind blowing driving experience…

The new Exige S is the latest in a line of high performance, track-focused racing cars from Lotus.  Encapsulating the ethos of Colin Chapman (lightweight, agile, power to weight, ride and handling), the Exige has a strong and loyal following among racing aficionados, and can often be seen at open track days giving more powerful and more expensive sports cars a run for their money.

In 1999 Lotus created a track only Lotus Sport Elise used in a one make series racing, this led to a road car version, named the Exige from the French word ‘exiger’ meaning ‘to be demanding’.  The first road based Exige was essentially a raw race car for the road, with a highly tuned 1.8 litre VHPD normally aspirated engine producing up to 190 bhp.

The bodywork was borrowed directly from the Sport Elise and generated 80 kg of downforce at 100 mph from the massive front air dam and rear wing, and a roof-mounted air intake forced cooling air to the engine bay.  Weighing just 780 kg the Exige had a top speed of 136 mph and 0-60 mph acceleration in under 5 seconds.  Lotus had introduced a new genre of car, a useable track car that could also be used on the road, with 583 S1 Exiges built from 2000-2001.

Second generation launched in 2004

The series 2 Elise was launched in 2002 with a new chassis approved for the Federal market powered by a 1.8 litre VVTL-i engine, followed by a new Series 2 Exige in 2004 with more aggressive track-focused styling, a large rear wing and roof mounted airscoop. Fitted with a 189 bhp 1.8 litre VVTL-i engine that was capable of pushing the 875 kg Exige to 147 mph and from 0-60 mph in just 4.9 seconds.  In 2006 an even more powerful variant (the Exige S) was launched in which the engine was supercharged to provide 218 bhp and 215 Nm of torque, providing 0-60 mph acceleration of just 4.3 seconds.

With performance from the 1.8 litre supercharged engine pushed to 260 bhp in the cup 260 version in 2010,  engineers started to look for a new powertrain for future models, fortunately work had started on the Evora S, supercharging the 3.5 litre V6 in the standard Evora from 276 bhp to 345 bhp, an ideal choice for the next Exige.

Development programme

Exhaust system has an extra valve which protects the engine and provides a sportier exhaust note

A programme was launched to package the V6 into the Elise platform.  An Exige mule car with the engine and gearbox of the Evora was created to test the concept and identify areas that would require re-engineering.  Due to the width of the rear Evora module (which includes rear subframe, powertrain and suspension track), it was not possible to style or match the wide rear of the vehicle to the narrower mid-section and front.  So a new rear subframe was engineered to fit the V6 engine, keeping the wheel track width to a minimum, to be in keeping with the Elise chassis.  Along with the rear sub frame, wider track and larger tyres at the front to deal with the extra power and torque of the engine had to be identified and developed.

The supercharged V6 engine delivers 345 bhp and 400 Nm of torque, so the engineers identified larger and wider tyres to accommodate the huge power and torque to the rear wheels, with tyre size and width increased at the front to 205/45 R17, and the rears to 265/35 R18.

Lotus DPM has four modes (Touring, Sport, Race and Off)

With engine, packaging, tyre choice and styling decisions made, work started on selecting the make and compound of tyres and determining the required steering ratio.  Due to the longer wheelbase the steering speed was felt to be too slow, so this was increased to improve agility and alertness.  For the tyres Pirelli was chosen as the supplier selecting the Pirelli P-Zero Corsa and Trofeo tyres as the best application for the new Exige, but as there were no Corsa tyres in the size Lotus required, Pirelli started development on bespoke Corsa tyres for the Exige.  Tyre selection and setup is important to any car, and a key goal of the Exige programme was to ensure the driver had maximum confidence in the car’s capabilities, feeling the limits of grip.

Pirelli P Zero Corsa tyre on the left and Pirelli P Zero Trofeo tyre on the right

Whilst Pirelli worked on the new tyres, Lotus began winter testing in Sweden, working with Bosch to calibrate the vehicle’s ESP systems (forming Lotus DPM).  An additional car was built so that ride and handling work could be started.  Developing the car at Idiada in Spain, Lotus Ride and Handling teams started work on the springs, damper rates and anti-roll bar tuning.  New lower friction gear cables and reduced flywheel mass to reduce inertia were developed to provide an improved gearchange.  This transformed the performance with the improvements also incorporated into the MY11 Evora upgrades and the Evora S.

As development progressed, Pirelli issued three submissions (each submisssion incorporating up to eight different specifications of compound and construction) of development Corsa tyres for testing which progressed at the well known testing circuits of Idiada and MIRA.  Testing incorporated calibrating and developing software updates to the ESP system from Bosch, as well as different suspension set-ups and brake testing, with additional brake fade characteristic testing carried out at the Stelvio Pass in Italy.

On Pirelli Trofeo tyres, the vehicle really came to life on the track, the tyres providing increased response, higher grip and improved body control, the trade-off being higher wear rate and firmer ride, whilst the Corsa tyres proved to be exceptionally good, offering very capable all-round use, with improved wet weather grip over the out going Exige due to the aggressive front tyre treads dispersing surface water therefore enhancing the grip of the wider rear tyres.

2012 EXIGE S COMPARED TO EXIGE CUP 260

The Exige S is available with two suspension setups, standard and an optional ‘race pack’ setup, both developed at various locations including the Nürburgring, in Germany, where the team had the opportunity to fine tune the Sport suspension settings and further develop the new race mode DPM setting, optimised for use with the Trofeo and Corsa tyres.

From the start of the programme the ride and handling team were keen to improve the outgoing Exige’s award winning driving feel and handling as much as possible, and early comments on the new Exige setup were that it was not as focused as its predecessor, due to characteristics of the improved rear suspension design.  However,  further development work on the ride and handling ensured that the new Exige is true to its track-born roots and whilst not as extreme as the outgoing Exige Cup 260, the new Exige S is a competent road car and like all Lotus Exiges an unrivalled car for the track.

The 2012 Exige S

The new Exige S was unveiled at the Frankfurt Motorshow 2011 and Lotus has already taken a large number of orders.  The powerful engine, combined with the aggressive track-orientated design (with styling cues providing a route from the old cars to the future cars shown in Paris), the vehicle is true to its racing series roots, whilst the powerful engine and advanced DPM will enable more drivers to use the vehicle to its capabilities with greater stability and safety both on track and on the road.

With 345 bhp and a low vehicle weight of 1,176 kg, the Exige has a top speed of 170 mph, and can accelerate to 60 mph from standing in just 3.8 seconds. An Exige S Roadster concept was shown at the Geneva motorshow in March and the Exige R-GT starts its rally season in 2012 continuing the racing legacy of both Lotus and the Exige, a car born on the track yet at home on the road.

  • 345 bhp
  • 400 Nm torque
  • 3.5 litre supercharged V6
  • 0-60 mph in 3.8 seconds
  • 0-100 mph in 8.5 seconds
  • Top speed of 170 mph
  • Weight 1,176 kg
  • 236 g/km CO2
Author Paul Culley

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About lotusproactive

Lotus proActive is an e-magazine published quarterly by Lotus Engineering, covering engineering articles, industry news and articles from within Group Lotus (Cars, Engineering, Originals and Racing).

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