Introducing the ultimate Lotus Exige: the JSR550 Edition.
Calling on over ten years of Elise and Exige high performance road and race car preparation experience, and over 18 months development of this particular vehicle, the team at JSRacing have built what they believe is the ultimate road and track Lotus: the JSR550.
With an engine producing 542bhp installed in a vehicle weighting just 890kg (with all fluids and full tank of fuel), the power to weight ratio comes in at 609bhp per ton. To put that in perspective, 609bhp per ton is over double that of a 2009 911 GT3RS (302bhp/ton) and is 17% higher than that of a Bugatti Veyron (521bhp/ton).
Performance figures will be established shortly, details to follow.
Having campaigned their own Audi-powered, race-winning Exige in the Lotus Elise Trophy, the JSR team know exactly what's required to achieve the all important balance of performance verses reliability. When it came to building the JSR550, every element of the vehicle has been specified and developed to ensure both maximum performance, but more importantly: maximum reliability.
When the modified class of the Lotus Elise Trophy was outlawed two years ago, the JSR team took all their performance tuning and race experience and used it to develop and built the car you see here. With no race regulations limiting engine power output or component choice, the finished vehicle is pure, uncompromising automotive art.
Engine
Based on an Audi 20v turbo-charged engine, the engine in the JSR550 is hand built using brand new up-rated internals including: steel crank, forged rods and pistons, one piece valves and high performance assembly components. External components such as exhaust manifold, turbo-charger, exhaust system, engine mounts, fuel system and cooling systems have all been exclusively designed and developed with high reliability and high performance driving in mind. The 2.1ltr engine develops a massive 542bhp.
Transmission
A VAG-derived, JSR spec 6-speed gearbox bolts to the engine via a specially developed twin plate clutch. The ‘base’ gear set has been selected to provide both ferocious acceleration and a maximum speed of just over 200mph.
Suspension
Series 1 Elise/Exige models are known for not having the most reliable of wheel bearings – a problem compounded when track tyres and engine tuning comes into play. To ensure this isn’t a problem on the JSR550, the car features hybrid alloy uprights with uprated bearing/flange assemblies from a Series 2 Exige.
Featuring specially developed 46mm Ohlins 2-way adjustable dampers, the spring/damping/valving and geometry settings on the JSR550 suspension have been tuned specifically for a combination of road and track use in conjunction with the Audi engine and performance. With each vehicle being made to order, we can tailor the handling characteristics to your particular requirements and driving style.
Brakes
As you'd expect for a vehicle capable of very high speed driving, the brakes have been specified to cope with multiple decelerations from very high speeds. The front features AP Racing 6-pot calipers with 330mm 2-piece discs. The rear featurins AP Racing 4-pot calipers with 315mm 2-piece discs. Front:rear brake bias is adjustable from inside the vehicle and brake pressures are monitored and data-logged.
Body
The bodywork is based on that of a Lotus Motorport Elise race car, but modified to JSR specifications to achieve better air flow and the clearance required for the taller and wider wheels and tyres. Additional front splitter and rear diffuser have also been installed.
Wheels and Tyres
Original Series 1 Exiges had very little choice when it came to wheels, due to the unique stud pattern Lotus used. Because the JSR uses specially developed hubs/bearing/flange assemblies which feature a more common stud pattern, wheel choice is greatly increased. The vehicle shown here features Team Dynamics wheels of 17in diameter on the front and 18in on the rear (original Exiges featured 16 and 17in wheels).
Electronics
The entire vehicle electronic system has been designed with this vehicle in mind. The AIM dash display is linked directly to the vehicle’s Motec ECU which is fed every vehicle major vehicle parameter, from brake pressures, to gearbox temperature, steering angle, wheel slip, g-force and all engine temperatures and pressures. That data is used to ensure the engine is always performing exactly as intended and to enable the fully integrated launch and traction control systems. All actions are data-logged by the vehicle ECU, which is also linked to the onboard camera which displays vehicle speed and several other data feeds as part of its playback footage. Finally, an entirely bespoke vehicle wiring look and integrated Motec Power Distribution Module eliminate the need for any relays or fuses throughout the entire vehicle.
Interior
The integrated 6-point roll cage will hopefully only ever been needed as a mount for the on-board camera! Seat belts are race-spec 6-point harnesses and the seats is the vehicle shown are Tillet carbon fibre FIA approved models - but being a bespoke vehicle, there is a huge choice of options available.
