SOUND THE CHARGE
e deceived by the softer lines of the redesigned Esprit.
In the latest SE form it packs more of a punch than ever.
AutoCar 10th May 1989
by David Vivian, pictures by Stan Papior
Back in 1984, a Lotus Esprit Turbo competed in the 'World's Fastest Production Car' trial and came last. It was going to come last even before it broke. It broke with the strain of trying to look convincing against much faster and vastly more expensive exoticars that had been carefully prepared, as the organisers put it, 'to go exactly as fast as their makers intended them to'. In the event, this turned out to be considerably faster than anyone had managed to make them go before. But that's another story.
That the Esprit's presence was required at all at North Weald Aerodrome to arbitrarily slug it out over the standing kilometre with a Lamborghini Countach LP500, an Aston Martin Vantage and a Porsche 911 Turbo a contest it could never seriously hope to win was remarkable in itself. For all its efficiency, clever engineering and dynamic ability, the plastic flyer from Hethel had never, in this writer's estimation, quite earned first team selection, despite its terrific performance-per-£ value and unquestioned dynamic finesse.
The real point, however, is that nobody laughed at the Lotus. To punters in the paddock, it didn't seem to matter that it had just four cylinders and 2.2 litres to the Lambo's 12 cylinders and 5 litres. They breezed over its Austin 1100 door latches to dwell on the provocatively kicked-up tail lip, the sexy air ducts and, best of all, the little black and gold 'styled by Giugiaro' plate in front of each door. They didn't see a plastic shoestring supercar built in Norfolk by a one-time kit car maker but a glorious mid-engined wedge that was low, wide and hard to peer into.
Fast is, the Lotus won the beauty contest hands down. It wasn't cowed by the outlandish Countach yet it dazzled the 911 and the Vantage clean out of the frame. It may not have been the fastest or the flashiest but is was the most handsome.
Much has happened to the Esprit Turbo since then, of course. For one thing, it doesn't look the same. Restyled in-house towards the end of 1987, the paper-edge sharpness and dramatic angularity of the Giugiaro original have given way to a more fluid shape with softer sweeps, rounder edges and no acute angles to challenge the eye. Much of the audacious drama has ebbed away, yet since is was the very forcefulness of the styling that had started to date the Esprit, that's no bad thing. The evolved shape is all elegance, lightness-of touch and subtlety by comparison, verging on dare it be said oriental blandness around the nose. It doesn't flick your eyelids open the way the old design did but it is exceptionally well proportioned and beautifully clean.
'This straightforward expression of
function and good performance
conveys a correct clean feeling'
Andy Jacobson (Deputy General Manager Nissan Design)
All of which poses something of a problem when you need instant aesthetic aggression to signify a boost in performance of not inconsequential proportion. Never a company to leave potential unexploited, however, Lotus has gone ahead to produce the extravagantly winged and be-spoilered Esprit Turbo SE a head-down assault on the cosy Ferrari-Porsche domination at the edge of the supercar stratosphere.
Some thought that Lotus had taken the Esprit's 2.2-litre, turbocharged twin-cam, 16-valve four as far as it dare in HC 'high-compression' tune with 215bhp and 220lb ft of torque. This engine saw service in the final version of the old shape Esprit Turbo and was slotted straight into the new one. Despite the modest claimed improvement in Cd (down from 0.35 to 0.34), the new shape was clearly a lot cleaner through the air and massaged the Lotus's performance to good effect, hiking top speed from around 145 to 150mph and dropping its 0-60mph time to a couple of fractions over 6secs.
But Lotus tinkered with the engine again, this time adding a chargecooled turbo and semi-intelligent engine management system. The new 264bhp Esprit Turbo SE costs £42,500, has a claimed top speed of 163mph, is said to accelerate from rest to 60mph in 4.7 secs and to 100mph in a sizzling 11.5 secs. If these figures are confirmed and my couple of laps round Millbrook at an average of 157.8mph suggests that over 160mph is on the SE will find itself in elite company indeed. Sub-12 to 100 is beyond even the Porsche 911 Turbo and the number of production cars that can crack 5 secs to 60mph can be counted on the fingers of one hand. But none of them, to the best of my knowledge, runs on an exclusive diet of unleaded petrol and is fitted with a catalyst. What we have here is a 'green' engine with an almost unparalleled specific output of 121.5bhp per litre.
The combination of chargecooled turbo and high-tech engine management is responsible for reconciling such apparently disparate elements. Apart from the adoption of Mahle forged pistons with chrome plated crowns, there are no internal changes to the 16 valve, all-alloy 910S turbo engine. The boost in power and torque outputs by 14 and 17 per cent respectively are essentially the result of a fundamental rethink of the induction system and electronics.
Manufactured by Delco Electronics, the Electronic Control Module used in the SE is one of the most powerful automotive microprocessors available and, in conjunction with unique software algorithms developed for the chargecooled Esprit by Lotus, provides adaptive fuelling control which determines precise fuel flow for each individual engine to which it is fitted. It is an intelligent system inasmuch as it remembers and learns the acts on the basis of constantly updated information. Thus the adaption is an internally calculated modification to the basic programmed fuelling maps. The system does most of its 'learning' over the initial 15-20 miles of driving but will be making small adjustments throughout the car's life.
At the business end of the fuel system is the electronic multi-point fuel injection which provides additional fuel flow at high engine loads via two secondary injectors positioned in the plenum nozzle. The key to the revised induction system, however, is the liquid-cooled charge air cooler, an alternative to the more common air-to-air intercooling with comparable thermodynamic efficiency but notably better packaging arrangements.
'The Esprit has real road presence.
Stevens managed to bring an already
well-proportioned car into the '80s'
Andy Jacobson (Ford Design Director)
The chargecooler is engine mounted and connects the Garrett TB03 turbocharger compressor directly to the plenum nozzle. Little bigger than a box of cream crackers, the unit contains a series of air and liquid passages with internal finning designed to maximise heat transfer with minimum pressure loss. The cooling system is self-contained and forms no part of the main engine cooling circuit due to the different temperature requirements.
Ambient temperature is critical, however, to the performance of the chargecooler. The 264bhp engine rating is, in fact, the lowest continuous steady state output the engine can achieve in a hot climate. The management system is designed to take advantage of lower chargecooler input temperatures to provide an instantaneous power boost of up to 280bhp available for 30 secs during acceleration.
This is not a subtle effect. In the regular Turbo, boost pressure builds up swiftly and progressively to deliver clearly potent midrange acceleration. With the SE, though, there's a real, physical slam as the turbo gets a grip. If it's possible to sense anything with your neck muscles, the message here is almost painful: up to 100mph, the SE hauls as hard as anything this side of £100,000.
As you might expect, the engine revs with respectable smoothness and little obvious top end strain, but it never sounds like a supercar powerhouse. The clatter from cold is depressingly reminiscent of a Cortina with dodgy bearings and the engine rasps waspingly on full throttle, albeit in a muted and largely inoffensive fashion.
The gear ratios place third, fourth and fifth gears quite close together and consequently leave something of a gap between first, second the third. The SE nevertheless storms past 60mph in second on its way to 67mph at 7000rpm while third is good for 99mph. The power flows strongly, the only ripples being provided by a gearchange with a rather rubbery action and a tendency to graunch if shifts are rushed. The clutch is fine, though, its action being neither as weighty nor as abrupt as the arrangements of some Italian rivals.
Likewise, the SE adjusts its cornering balance more benignly than long-time sparring partner the Ferrari 328 GTB. Punch the throttle mid-bend and the chassis doesn't pile on understeer or twitch its tail nervously. It merely shrugs away the slug of turbo energy with a small sideways shuffle. The SE feels perceptibly less edgy on the limit.
Those looking for extra front end bite with the new car, however, are likely to be disappointed. The SE feels just as precise as its predecessor and locks on to a cornering line with iron conviction. But along with some of the previous car's steering weight and, heaven knows, it was too heavy a small degree of sharpness has been lost and, with it, that delicious sense of intimacy that was always an integral part of the Esprit's make-up.
In a sense, Lotus has sanitised the Turbo's responses for general comsumption. Given the chargecooled engine's sledgehammer midrange delivery, it's probably just as well, but a shade more resolution of the road surface at the helm would have been welcome. That said, the SE feels if anything even more stable and grippy than its less muscular forebears and while some of the credit for this must undoubtedly rest with the enhanced performance of the ZR-rated Goodyear Eagle tyres (215/50 ZR in front, 245/50 ZR 16 rear) specially developed for the SE, the crucial work has been Lotus's. Not just in fitting stiffer front springs and gas-filled dampers but in eliminating the front suspension's anti-dive characteristics to reduce pitching and improve ride. Best of all, is the reduction in steering castor angle. Parking is no longer like arm-wrestling with Sylvester Stallone.
The Turbo SE's ride combines almost pampering pliancy with great control. The body motion could always feel a little jiggly over small bumps and ridges around town, but the SE simply feels supple and composed. The brakes are powerful and tireless but a little overservoed and, somewhat alarmingly if you're not expecting it, tend to promote excessive camber sensitivity in the steering.
Little has changed on the inside. The low-slung facia is still dominated by its huge 'boomerang pod' instrument housing with a comprehensive array of clear and readable analogue dials sited in such a way that some of them are partly or wholly obscured by the rim of the 14ins, leather-rimmed steering wheel.
The push-push switchgear located on the pod's flanks, however, remains fine and enhances an already comfortable driving environment where the seats are well-shaped and supportive and the major controls convenient. Visibility to the rear is tolerable but the glass canopy that covers the rear buttress not only distorts the view but reflects body colour.
As for the styling, it's the same old story. Drastic plastic seldom, if ever, does anything to improve the aesthetic allure of a basically pure and graceful shape. Just look what happened to the Countach. You can still buy the ordinary Turbo, sans wings and spoiler but incorporating all the SE's chassis mods for around £11,000 less. If you're planning on entering any speed trials, however, you'd better opt for the SE. Its wing isn't as big as the Countach's but its kick is.