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Текст 45






LOTUS ELAN

 

The true depth of Colin Chapman's engineering genius is still being discovered. From his earliest days building Austin-based specials in a lock-up ga­rage, he was always ahead of the game. He developed an unsurpassed reputation for designing race-winning cars and became pre-eminent among British race car con­structors.

Chapman realised the need to develop road cars which would fund his true passion, motor racing. How­ever, despite levels of performance and handling that led the field, Lotus road cars were almost always de­ficient in build quality. Ironically, Chapman's earli­est true road car, the 1957 Elite, lost large sums of money for Lotus.

The Elan (рис. 24) changed all that. By 1962, Lotus had become the dominant force in virtually all singleseater racing categories and there was a strong demand for a road car which embodied the Lotus principles of light weight and efficient engineering. After his ex­perience with the glassfibre monocoque Elite, Chapman realised that what he didn't need was another difficult-to-make, expensive, raw semi-racing Car.

So the Elan was conceived to be a true sports car but one with practicality and ease-of-construction at the top of the agenda. Another glassfibre monocoque design was ruled out, so instead Chapman used a back­bone chassis. This idea was not new (it had been seen in Edwardian times) but the method of its construction was. The Elan didn't use a steel tube type chassis but a folded pressed-steel sheet forming a single girder. The lightness and rigidity of this set-up so impressed Chapman that he began using it on his Formula 1 cars. Soon all Fl constructors had copied him.

The backbone split at the front into a two-pronged fork embracing the engine/gearbox and leading to the front Suspension. A shorter fork at the rear carried a cross-member on which were mounted the rear Chapman struts. The suspension was by front wishbones, coil spring/dampers and an anti-roll bar, using pro­prietary parts where possible. The rear was independ­ent by struts and coil-sprung wishbones. Disc brakes were fitted all round.

As for the body, this was a glassfibre open structure which contributed little to the rigidity of the chassis. It was a one-piece shell which bolted to the chassis and featured pop-up headlamps, which were a great novelty at the time. Overall dimensions were very compact and the first Flans were strict two-seaters. They were all initially open-topped, although an optional hard top was offered from May 1963.

 

 

Рис. 24

 

The Elan was launched at the 1962 London Motor-Show at £ 1, 499 complete, although most buyers elected to save purchase tax and build their own car from a complete kit, priced at £ 1, 095. Thus it was not a cheap car but it was certainly one of the most desir­able sports cars of any description in 1962.

Lotus launched the Elan with a 1498cc twin-cam engine based on the Ford Cortina block. When the in­ternational racing class was raised to 1600cc, Lotus expanded the engine to 1558cc, recalling ail the 22 Elans already built with the smaller engine. In this definitive form, the engine developed 105 bhp, enough for 115 rriph and 0-60 mph in 8.7 seconds.

However, it was in roadholding and handling that the Elan excelled. It became a benchmark against which all others were judged and even today it has enough ability to raise the eyebrows of hardened road-testers.

There were many early problems, like flaking paint, poorly fitting trim and criticisms of the rub­ber doughnuts on the drive-shafts, which were quickly replaced with superior Rotofiex joints. Engine noise at high speed was also a concern, which was remedied in 1965 with the option of a higher final drive ratio.

In late 1964, Lotus introduced a Series 2 ver­sion incorporating larger brake callipers, a better interior arid optional centre-lock wheels. The Series 3 of the following year had an extended boot lid, higher final drive and could be ordered as a fixed-head coupe as well as a drophead.

The 1966 SE (Special Equipment) became the best Elan to date, boasting a 115 bhp engine, close-ratio gearbox and servo-assisted brakes. The final Se­ries 4 version (1968) had flared wheel arches, rocker switches and was available, from 1971, in ultimate Sprint guise, with a Tony Ruddmodified ‘big valve’ twin-cam engine developing 126 bhp. The Sprint needed a strengthened differential and drive-shafts to cope with its performance (124mph and 0-60 mph in 6.7 sees), and was easily recognised by its two-tone paint scheme. The two-seater Elan lasted until 1973.

Inevitably the Elan made it on to the track. Lo­tus built special racing versions with lightweight bodies arid modified suspension to improve roadholding, which were called 26R. The drivers included Jackie Stewart, Stirling Moss, Mike Spence and John Miles, the latter achieving such great success he was given a place in Lotus' Grand Prix team.

There is a second chapter in the Elan story. Chapman launched another road-going Elan in the form of the ‘Plus 2’, or family man's Lotus. This was first introduced in 1967. The primary reason for the exis­tence of the Elan +2 was to provide an extra pair of seats for children up to teenage years. In concept and layout it remained very much an Elan but it was larger in every way.

The backbone chassis idea was kept but it was bigger. To compensate for the increased bulk, holes were drilled in the steel to reduce weight. The body­work was still glassfibre but it was substantially en­larged, gaining a foot in length and 7in. in width. It was substantially redesigned, featuring a new slop­ing nose, much larger boot and fastback roof (all +2s were fixed-head coupes). The interior was also im­proved, having a more comprehensive dash.

Mechanically, the story remained much the same, although the +2 became the first Lotus to gain a stan­dard brake servo. The same 118 bhp 1558cc twin-cam en­gine was used. Although the weight penalty over the standard Elan was considerable (46.8 cwt/850 kg to 14 cwt/710 kg), performance did not suffer too badly, probably because of superior aerodynamics: A +2 could reach 121 mph and 0-60 mph in 8.2 sees.

In 1968, the family Elan was uprated to +2S specification, gaining better trim and more equipment, such as fog lamps. It became the first Lotus that could not be bought in kit form, only being sold fully-built.

To return the Elan +2 to two-seater performance levels, Chapman introduced the +2S/130 in 1971, which had the 126 bhp big valve engine of the Elan Sprint.

Elan +2S/130s are easily spotted by their self-coloured silver roofs. The final metamorphosis came in late 1972, when a five-speed gearbox was offered as an option. By 1974, changing type approval regulations made it uneconomic to continue producing the Elan. In any case, by then Lotus had its brand new 2.0-litre Elite in a bid to move upmarket. The 90s Elan was a different animal and never quite rekindled the spirit of the original.






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