The new-style car, coded X180 at Hethel, was launched in October 1987, with deliveries beginning almost at once. Because this was merely a new bodyshell on an existing and well-proven chassis, with a new gearbox/transaxle, this was an excellent, low-investment way of developing a new model. The progress from concept to production had taken only 15 months.
The problem if it was a problem was that in spite of its more rounded character, the new car looked so very much like the old. Compared with the now-obsolete and sharp-edged Giugiaro style, the X180 was more rounded, smoother and softer than before. Its proportions were virtually the same, but it was as if the hot sun had been allowed to play for hours on a rather pliable model stack. One easy way to pick the new design was by its use of a brand new style of cast alloy road wheel.
The aerodynamic impression of shapes, incidentally, can be deceptive. Although the new car looked much smoother than before, its drag coefficient was in fact slightly higher, at 0.35 instead of 0.34.
Cohn Spooners team of designers, led by Peter Stevens, had solved a near-impossible task with great style literally. The aggressively sharp-edged Giugiaro design which had been truly in vogue in the Seventies but had been outdated by design trends in the Eighties, was replaced by something more sensuous, more gently rounded and more sophisticated yet it sat on the same backbone chassis, with the same wheelbase and track dimensions.
As with other modem Lotuses, the new style was designed to be produced in two large halves top and bottom mainly from glassfibre, but with some local Kevlar reinforcement, using the companys patented vacuum-assisted resin-injection (VARI) process. The style was created in-house, at Hethel. Giorgetto Giugiaro, I understand, was not asked to offer ideas, and probably never even saw the new shape until it was unveiled.
Although the profile of the new body varied by no more than an inch from the old at any point, it looked very different. All key lines were rounded off, rather than razor-sharp, most details such as the fuel-filler flap, and the air scoops for the engine bay, which were in the sill mouldings ahead of the rear wheels were much tidier than before, front and rear bumpers were made in knock-resistant mouldings, and in spite of initial impressions every single pane of glass was a new shape and size. The new body featured a lift-out panel in the roof, this being either in a Nomex honeycomb material, or in tinted glass.
There were several basic visual differences between the normally-aspirated and the turbocharged types. Each car had its own special type of cast alloy road wheel though the same tyres were shared between types while the Turbos front end had extra driving lamps and a different front-end air intake. The biggest and most obvious difference was clear from the three-quarter-rear aspect. Both types of car featured neatly detailed flying buttress panels from the rear of the doors to the flip-up spoiler on the tail, but only the turbocharged car filled in most of that recess with a large sheet of glass to give what Lotus claimed was a tunnel-back feel. The Turbo also had a different rear lower body, with a carefully-profiled under-tray/spoiler to act as a scoop to help extract hot air from the engine bay and the brakes.
Inside the car there was significantly more legroom and passenger space in general but this was still a small two-seater coupe cabin because there was a limit to what Grand Prix designer John Cooper would call the Albert Hall effect which could be achieved. Instruments and the panel were new, there was a better ventilation system which was sorely needed, as all hot-climate Esprit owners would no doubt agree yet this was still not a car in which tall, particularly well-built drivers could get comfortable.
Facelifts, in general, do not always work very well, but the X180 process was in any case much more than a mere facelift. It was a complete restatement of the Lotus mid-engined theme, and it worked out extremely well. The designers had worked round the car in great detail, producing a neater and more integrated solution to almost every task.
The new car looked so good that it was a temptation to go back to the old type, criticize slots, flaps, lines and features and say to oneself: How could we ever have put up with that?. It wasnt heresy, but of how many other Giugiaro designs would one even begin to be critical?
Though little could be done about the overall size of the two-seater cockpit particularly as no changes had been made to the central backbone, or to the height of the chassis pressings the view from the drivers seat was little different from before. There was a new and more integrated facia design dominated by VDO instruments, the roof panel could be removed though surprisingly few owners seemed to take advantage of this feature and improvements had been made to the ventilation system.
Mechanically the new-shape Esprits were very similar to those of the 19867 HC models which had just been made obsolete which is to say that for normally-aspirated cars the 172bhp engine was standardized, while for the Turbo there were two different types, one with Dellorto carburettors, the other with Bosch K-Jetronic fuel injection. There was one major exception but only on non-Federal-market cars at first. Instead of the familiar Citroen/Maserati type of five-speed gearbox, Lotus had to find a replacement that would fit, which was robust enough and suitably packaged.
Because the number of powerful European cars with combined gearbox/final drive transaxles was increasing all the time, Lotus had no trouble in finding a new supply. Links with Renault of France, which had flourished in the Sixties in the case of the mid-engined Europa, were revived, and Lotus chose the robust Renault 25/Renault GTA type of five-speeder instead of the old Citroen type. Surprisingly, though, the Citroen gearbox was retained on USA-market Esprit Turbo HCPIs for the first year or so.
The old Citroen gearbox had served Lotus well and was still available from France, but all the mainstream Citroen! Peugeot models which had used it had dropped out of production. Soon, Lotus reasoned, the French company might want to close down supplies. The 25/GTA-type gearbox, on the other hand, was relatively modern, and had an assured future. This gearbox, incidentally, was a very versatile unit. In the sporting GTA itself it was arranged to be ahead of the final drive unit, and driving back to it. In the Renault 25, it was behind the line of the final drive, and driving forward to it! For the new Esprit, therefore, where the gearbox was behind the final drive, there were strong similarities to the Renault 25 type of installation.
Here, for comparison, are the ratios of the new transmission and the old:
The internal gearbox ratios in the Renault 25 and the Renault GTA incidentally, were exactly the same as those supplied to Lotus, which made parts supply even easier to ensure. The V6-engined Renault 25 also had the same final drive ratio, but that of the Renault GTA was significantly higher.
There was one other significant mechanical change, which was forced upon Lotus. When Renault were developing the new gearbox, they had decided to use outboard disc brakes on their cars. Accordingly, there was no way that Lotus inboard discs could be fixed to the new casing. The old Esprit, therefore, had always used inboard disc brakes, fixed to a Citroen transmission intended for such a fitting; the new car had outboard discs for the very first time.
Clearly the Esprit restyle had arrived at exactly the right moment. Backed by the might of General Motors, Lotus self-confidence was glowing as never before, and they had recently acquired control of the Lotus sales/distribution organization in the USA. This was moved from New Jersey (west of New York) to a brand-new facility at Atlanta, Georgia.
The company was making good profits, the still-secret new Elan was on the way and sales shot up. At the London Motorfair in October 1987 Lotus announced that they had taken orders for 371 Esprit Turbos, worth £8.2 million.
In 1987 a total of 462 Esprits new type and old type combined had been produced, but helped along by the new style this total rose to no fewer than 1,058 in 1988, which was easily an Esprit record. In fact this was an all-time Esprit record, for although there would be another major new development in 1989, Lotus never again built more than 1,000 Esprits in a year.
In the first half of 1988 UK sales totalled 271 cars, while exports rose to 311, of which no fewer than 172 went to the USA. At the end of 1988 those figures had risen to 572 UK sales and 323 USA sales.
new-style Turbo was a genuine 150mph car and this, allied to overall
fuel consumption of around 20mpg (Imperial), made the latest car an
intriguing proposition. Purists still complained about the restricted
cockpit space, the need for power-assisted steering and the fact that
the car did not have ABS anti-lock braking, but even they could drive
the Esprit faster than almost every other supercar, and still arrive
at the end of a trip with a big smile on their faces
A month later Road & Trach tested a USA-specification Turbo, headlining its report: Hethels hardy perennial blooms again. There was a lot more: Throw the Lotus into a corner and the first thing you notice is nothing. Other than quick, accurate steering ... Its an exotic toy for people who not only can afford it, but also will appreciate its particular brand of performance as an extension of the Lotus tradition, and a handsome one at that.
By this time the Esprit Turbo had taken over the majority of sales in all markets. It was, of course, the only Esprit to be sold in the commercially important North American market, yet it was now such a success that it was overshadowing the normally-aspirated Esprit almost everywhere. Sales of normally-aspirated cars gradually fell away from 176 in 1988 to 90 in 1989, and to a mere 22 in 1990, after which the model was allowed to fade out gracefully.
The development engineers, on the other hand, redoubled their efforts to make the turbocharged cars ever better. In 1988, 1989 and 1990 there would be major improvements to the engine and to the chassis and there was even time for a special Italian-market model to be launched, too.
It was remarkable, at a time when the front-wheel-drive Elan project was being urged towards its launch, that there was still opportunity to work so hard at an established design. The important chassis change came in mid-1989, when what Lotus colloquially call the Eagle chassis was introduced. The basic design was not changed, but there were revisions to suspension geometry which eliminated anti-dive, and a reduction of the front castor angle. Along with an increase in bump travel, the use of stiffer front springs and 16 inch diameter rear wheels but the retention of 15 inch front wheels this showed signs of a radical rethink.
Turbocharged engine developments
work which went into engine improvements in the same period needs
explanation. According to the list supplied by Lotus, 10 different
versions of the turbocharged car were produced between 1987 and 1991,
along with the much-modified Xl 80R SCCA race car, which is covered
more fully in Chapter 7
In the period just detailed, the first major change was to specify a different type of fuel injection system what was called Lotus/Delco MPFI (Multi-Point Fuel Injection) instead of the original Bosch system. The key to this change was the word Delco, for Delco was a familiar General Motors brand name, and Delco systems had been in use on North American GM engines for some time.
Even more than the Bosch K-Jetronic system, which was a long-established fuel injection package used by many other car makers, this was attuned to all modern and demanding exhaust emission requirements. When the time came, too, GM and Delco would be able to cope easily with the require-ments for catalytic converters.
It was a great bonus for Lotus that the Delco system also liberated more power (228bhp vs 215bhp) and more peak torque (2181b.ft at 4,000rpm compared with 1921b.ft at 5,000rpm) than the Bosch system had done.
The major leap forward, however, followed in mid-1989, when Lotus finally made a charge-cooled engine available. To be frank, it was long overdue, for although the company had been one of the very first to put a turbocharged road car on sale, they had then fallen well behind other manufacturers as they refined the technology further.
The theory of charge-cooling, or intercooling, is simple enough. Compressed air forced out of a turbo compressor is hot, and if it can be cooled before entering the engine the volumetric efficiency is dramatically improved. Cooling is done through a radiator either an air-air type, or an air-water type.
As might be expected, the Lotus installation was neat and effective. In this case the charge cooler was mounted on top of the engine, and the coolant was water, this being in a self-contained system, circulated by an engine-driven pump to a front-mounted radiator.
This, however, was merely part of a comprehensive improve-ment package, which also included Lotus/Delco injection and the ability to run on lead-free fuel, a catalyst being standardized. Not only did all this help push up peak power to 264bhp (DIN) at 6,500rpm, but there was also a transient over-boost facility which allowed usage of 280bhp at 6,500rpm for up to 30 seconds of hard acceleration.
Two years after this charge-cooled engine had been launched, a further variant was introduced, this being a 2-litre version, initially for sale only in the Italian market. The rationale was fiscal, not technical, for in Italy much higher motoring taxes were applied to cars with engines of more than 2,000cc.
There were precedents for this move Ferrari, Maserati and Lamborghini had all offered smaller-engined versions of their cars from time to time, though in no case had sales come up to expectations. The development cost of producing a smaller-capacity engine which actually used the self-same crankshaft as the original Type 907 engine had done in the Seventies was small.
With the introduction of the charge-cooled turbo engine, Lotus claimed the title of the worlds highest specific output for a road-car engine (121bhp/litre), though this was not likely to be held for long.
By the early Nineties the famous 16-valve engine had been on the market for 20 years, but Lotus clearly thought more potential was still locked in there. In 1992, as this book was being prepared, the first of an entirely new design of aluminium cylinder block, more rigid than ever before, was phased into production.
Esprit improvements 1988-92
In the spring of 1989, when the charge-cooled engine was put on sale, Lotus also introduced a series of chassis and engine changes to the Esprit. The Eagle chassis, so called because of the exclusive use of Goodyear Eagle tyres, which is easily identified by its use of 1 Sin diameter front and 1 6in rear wheels, was standardized on all Esprits at this time, but the derivative with the 264bhp charge-cooled engine became the Turbo SE (SE = Special Equipment). The cost was a massive £42,500.
The SE not only had far more performance a top speed of 159mph and 060mph in 4.9sec, which was remarkable by any standard and equal to the performance of the Porsche 911 Turbo of the period, but there had been further changes to the aerodynamics. At the front there was a deeper front bib spoiler, the sills and their associated air intakes to the engine bay had been reprofiled and, for the first time on an Esprit, there was a small free-standing spoiler on the tail. Air conditioning and a tilt/removable glass sunroof were also standard.
the cockpit, there was more obvious luxury perhaps an attempt
to justify some of the extra cost of the car. As Autocar & Motor
stated in its road test: The SEs all-leather cabin has
more of a quality ambience than the regular Turbos,
an impression helped along by the large slab of burr elm surrounding
the instruments and switches ... This, by the way, was another
enthusiastic road test: With the Turbo SE, Lotus has made a
break for the big time and has succeeded admirably in all the most
obvious respects. To many eyes the Esprit has always looked the part
and now those looks are matched even surpassed indeed.
The SE is fabulously rapid and enormously capable
The most important mechanical improvement was that three-channel ABS anti-lock braking was finally adopted though not the power-assisted steering for which the pundits had been nagging for some time while for the British market this signalled the point at which three different models were briefly available. Note the model names carefully:
215bhp, Dellorto carbs £34,900
By this time, however, the Lotus factory and the Lotus dealers could no longer give the Esprit their full attention. They were too bound up in the front-wheel-drive Elan, which had been on volume sale since April 1990, to think of much else. This was also the point at which British economic recession began to bite in earnest, and when Lotus should have realized that the Esprit was beginning to look expensive. Perhaps this also explains why the Esprit S had such a short life for it was dropped after only a year.
Twelve months later, and at a point when the front-wheel-drive Elan still appeared to be selling very well indeed, more Esprit changes were phased in. Not only was there a very significant improvement to the cabin packaging of all types, but the SE model received an extrovert new styling package which was claimed to reduce understeer and raise the top speed.
From this point, all Lotus cars were provided with a three-year unlimited-mileage warranty experienced, not to say cynical, Lotus owners thought this was likely to be a very expensive deal for Lotus! and no doubt partly to allow for this the UK prices were raised yet again, with the price of the flagship SE ni.odel soaring to £48,260.
Somehow or other the cabin had been repackaged and made more spacious. Compared with earlier cars there was an extra 5.6in of headroom, 1 .6in more legroom and up to 3.2in more clearance between the seat cushion and the steering wheel rim. A repositioned cabin/engine bulkhead made the cabin 1 .2in longer overall. There was a revised pedal box which gave shorter pedal movements and the centre tunnel had been slimmed down to allow wider seats to be fitted.
Added to this was the provision of doors which opened by an extra 1 Sdeg and if this does not sound much, it equated to an extra 9in at the rear end of the doors.
The principal visual changes were only applied to the SE type, the official reasons being twofold: to add front-end downforce to cut the understeer, and to improve rearward visibility. The glass-back which had featured on X180 types since 1987 was abandoned, the original small spoiler of the SE was no longer fitted, and in their place was a larger and free-standing rear aerofoil, mounted on pylons. To balance this, at the front there was an extra rubber lip under the existing bib spoiler.
claimed that the overall effect was to improve downforce at higher
speeds, to cut the drag and to raise the top speed to no less than
Except for the Lotus Omega-Lotus Carlton assembly shop, by the autumn of that year the Esprit was the only Lotus car in production at Hethel, but in such low numbers that the factory seemed almost to be a ghost town.
What future for the Esprit?
In a book like this, and especially where Lotus are concerned, making predictions is a dangerous business. Accordingly, I can only summarize where the Esprit stood as the end of 1992 approached.
Immediately after the Elan had been killed off in June 1992, Lotus Managing Director, Adrian Palmer, made it clear that Esprit assembly would continue indefinitely, and that several significant developments were already in the pipeline.
On the one hand, the rumour-mongers told us, even faster super-Esprits, with different and more powerful engines, would be announced. That, however, was not likely to increase the volume of sales.
The other strong possibility, it seemed, was for an entry-level Esprit to be developed, one that had a much cheaper engine, probably the first not to have been built at Hethel. If the cars retail price could be reduced significantly, this might boost sales quite dramatically.
Favourite, it seemed, was the brand-new 2.5-litre S4deg V6 unit which General Motors had just revealed, and which would go into series production in 1993. This was originally intended to power Opels and Vauxhalls, and was a torquey, normally-aspirated engine with 167bhp.
In the early Nineties it seemed as if Lotus were determined to maintain the Esprit pedigree, and to improve it further in future years.
from 'Lotus Since the 70s' by Graham Robson