lotus exige - the handling benchmark
purity of esssence
Many Now Acknowledge The Lotus Exige As The Industry's Finest Handling Sports Car. How Have The Norfolk Company Created Such A World Leading Car On Such A Tiny Budget? We Get On Track With Matt Becker, Principal Engineer (Vehicle Dynamics) To Find Out
Druids Corner at Oulton Park looked innocuous enough on the sighting lap, but what seems a straightforward undertaking at 40mph suddenly concentrates the mind somewhat when it's approached at three-figure speeds, engine nudging the red line and with the accelerator planted against the bulkhead. Brake while blipping the throttle, snick the gear lever across the gate, off both clutch and brake and accelerate through the corner. The steering goes a little light to warn you that you're approaching the limits of the car's grip and without thinking, you apply just half a hand of opposite lock before it weights up again and you bury the throttle for the short 'straight' down to Lodge Corner. Many cars would be a smoking heap of salvage in the Armco barrier at this juncture. Fortunately we're in a Lotus Exige.
Recognised by many industry observers as a benchmark of handling excellence, the Exige is a car rich in detailed feedback. Riding with me today is Matt Becker, Principal Engineer (Vehicle Dynamics) at Lotus to highlight a few of the reasons why the Exige has developed into such an impressively capable sports car. One of the reasons Lotus has developed such a reputation for handling expertise is due to the fact that the chassis engineers work as a small cohesive unit, sharing information and thus ensuring that each component crucial to handling works in harmony with every other.
"The steering is a delight, Lotus knowing not to mess with a winning formula"
Of course, it also helps that right outside Becker's office window lays Hethel's notoriously arduous test track, bringing a whole new meaning to rapid prototyping and testing. Whereas many large companies will strike a deal with several tyre manufacturers to buy huge consignments of tyres off the shelf, for the Exige project the Yokohama tyres were developed especially for the car. This means that the sidewall stiffness is just right for a car that tips the scales at less than 900kg. Get this right and the steering feel will be massively improved, helping ham-fisted guys like me to smoke around Oulton Park without 'going agricultural' as would normally be the case.
We brought along a lightweight car from a rival manufacturer that used tyres more commonly seen on cars like Subaru Imprezas and Mitsubishi Evos and the difference was night and day. I'd wager the force feedback steering wheel on my Sony Playstation offered better steering feel. Becker talks at length about consistency of effort and consistency of response from the steering system. It's vitally important not only to get out what you put in, but to maintain an uninterrupted stream of communication via the steering to those four palm print sized contact patches of rubber.
Another reason the Exige is so feted is due to the power delivery of its 1.8-litre Toyota engine. After first being turned down by Toyota, Becker was able to convince its top brass to let Lotus use the four-cylinder 16-valve VVTL-I engine as well as the C64 six-speed gearbox. Thanks to a compact metal-matrix composite alloy cylinder block, this engine is featherlight, making a nice fit with Lotus' corporate value of adding less weight. The mid-mounted transverse unit is naturally aspirated with double overhead camshafts and hydraulic tappets. The all-aluminium six-speed gearbox was specified with the closest ratios and gear set available from Toyota. The engine-management system, bifurcated exhaust down pipe, and gearshift mechanism were developed by Lotus.
The VVTL-i system helps the torque output peak at 138 lb/ft (187 Nm) with peak power of 190bhp. The biggest powertrain challenge for Lotus engineers was development of the engine-management system. "It was a potential deal breaker with Toyota if we weren't able to prove that we were capable of developing our own engine-management system," said Becker but they were confident due to the fact that controller development is one of Lotus' core competencies.
Although the engine kicks out exactly the same power as the mechanically identical Elise 111R, the chassis development crew at Hethel have been given carte blanche to turn the Exige into the best track car money can buy. Spring and damper rates go up by ten per cent and - like its predecessor - the car gets special Yokohama tyres specially tuned to the enormous lateral forces it's capable of generating. Drive the car fast and tidily in the dry and you'll never get near the tyre's level of adhesion. It's only under deliberate provocation that the car can be made to slide, and even then it's almost slow motion.
Gone is the clanking gearbox of the K-series cars, the Toyota 'box making gear changing a delight. Another improvement that may have the purists grumbling into their real ale is the fitment of anti lock brakes. Offering ferocious stopping power, the brake pedal feels a little long in its travel, which makes heel and toe downchanges a little difficult. Becker attributed this to the fact that hard circuit use had made the pads a little banana-shaped. Uprating the brake pad material was one of the first priorities on his tick sheet for improving the Exige.
Some have questioned why they should spend £2,000 over the price of an Elise 111R - a car that shares the same engine and gearbox and is lighter and therefore fractionally quicker in a straight line - for the Exige, a vehicle you can't see out the back of and which loses the Elise's soft top roof. A full 80kg of downforce at 100mph generated by the Exige's wings and splitters is one reason. Add wider tyres for higher grip levels, recalibrated Bilstein dampers and snubbers fitted to the forward bushes of the lower wishbones and you have a car with a far more focused agenda than any series production Elise. I was a little hazy on the reason for these snubbers but Becker pointed out that they improved the car's suppleness over sharp bumps. I'll remember that next time I drive an Exige out of the Nurburgring's infamous Karussell.
When it comes to road and track performance, it would be a very hard taskmaster who found fault with the Exige. There may be some who feel that the Exige should justify its price tag by offering a clear horsepower advantage over the range topping Elise, but that's the role of the supercharged Exige 240R. You can tell Becker knows a lot more about plans for the Exige but isn't letting on. A pang of jealousy is replaced by sympathy. This guy's job depends on improving the Exige. Best of luck.