1969 Lotus 7 Twin Cam SS – celebrating six decades

Drive-My and Malcolm Griffiths

60 years of the Lotus 7. Celebrating six decades with a twin-cam. It’s 60 years since Colin Chapman launched the Lotus 7 – and it’s still being made by Caterham. Octane celebrates by driving a seminal Twin Cam SS. Words Glen Waddington. Photography Malcolm Griffiths.


7 RULESFOR LIFE CELEBRATION! 60 YEARS OF THE LOTUS 7


Certain years are etched upon the mind with greater clarity and definition than others, especially when we’re talking car launches. Take 1962 as an example: the Ferrari 250 GTO, the MGB and the Ford Cortina were all released that year, each an icon in its own distinct way. Or how about 1948? That year saw the Citroën 2CV, Jaguar XK120, Morris Minor, Porsche 356, the Bristol 401, even the Tucker 48, all unleashed on an unsuspecting world just beginning to recover from the calamity of war. Next year will mark some incredible 70th anniversaries.


1969 Lotus 7 Twin Cam SS road test

1969 Lotus 7 Twin Cam SS – test drive

But now turn your mind to 1957. Six decades ago. A few remarkable cars, not least the Fiat 500, though the Lotus Elite, Lancia Flaminia, Mercedes 300SL Roadster, Aston DB MkIII and Maserati 3500GT that were launched the same year don’t quite resonate like the swell of seminal groundbreakers that exploded onto the scene nine years before.

One car stands out, however, as much for its longevity as for its importance at the time. After all, Colin Chapman’s Lotus Elite was arguably a greater technical achievement, a car more in line with some of those 1948 epics in every respect bar cultural significance. Meanwhile, elsewhere on the Lotus stand at Earls Court in 1957 stood the 7. A tiny, spidery roadster, more clubman’s special than roadgoing sports car, which achieved Chapman’s ideal of lightness – for handling perfection and to make a little power go a long way – by being dainty and minimalist, rather than employing a structural method so outlandish that, in the case of the Elite’s glassfibre monocoque, it went straight to the end of the cul-de-sac with no sane followers.

Not so the 7. Now, 60 years on, it’s still in production, as a Caterham rather than a Lotus since 1974, and recognisably the same car despite myriad improvements, departures and the odd blind alley since. The 7 followed on, naturally, from the Mk6, Lotus’s first ‘series production’ car, available in kit form since 1952 following Chapman’s self-made rudimentary trials cars and sports racers. At its heart was a lightweight spaceframe chassis, to which the builder would add Ford Prefect suspension components and running gear. The Mk6’s popularity – 100 were built in its first three years – established Lotus as a manufacturer and gave Chapman the confidence to pursue his burgeoning genius as a racing car designer.


1969 Lotus 7 Twin Cam SS - celebrating six decades

1969 Lotus 7 Twin Cam SS driven

Crucially, the 7 followed the Mk6 in its simplicity, with stressed aluminium panels over a spaceframe chassis that was closely related to the Eleven racing car’s, all of which could be supplied in kit form for the home builder – or you could buy one ready-built by Lotus, for which the launch price was £1036. Building it yourself, however, meant you could avoid purchase tax and save yourself £500 in return for your labour. If you followed that path, you had to bear in mind that the Inland Revenue had decreed that no assembly instructions could be included – but there was no rule about ‘disassembly’ instructions. Customers simply had to follow them in reverse…

Drum brakes and a Burman steering box were combined with a Nash Metropolitan live axle and coil/wishbone front suspension, typically with 1172cc Ford sidevalve power, though options later included a Coventry Climax engine, or even BMC’s 948cc A-series, and the steering box quickly gave way to the Morris Minor rack-and-pinion set-up, also used to terrific effect in the Austin-Healey Sprite.

That latter change alleviated the terrible contortions forced upon the driver trying to operate the clutch in the earliest cars, as the steering column goes through at such an angle between clutch and brake pedals that space for your left foot is restricted to the extent that you’re better off driving barefoot. With the rack-and-pinion system, the column was handily lifted out of the way, though slim driving shoes are still a must. Chapman, though a bit of a yo-yo with his weight, was compact at 5ft 9in. He didn’t design cars for giants.

Yet we are talking about a giant-killing sports car, one with proprietary mechanicals and a measly 40, maybe 50bhp to shove it along. ‘Chunky’ Chapman’s obsession with weight (the car’s, not his own) was the key. At Earls Court in 1957, Lotus’s show car weighed-in at a mere 329kg. A driver weighs a quarter of that.

More modifications followed during the 7’s 16 years in production as a Lotus. The Series 2 arrived in 1960, with a simplified chassis, better location for the rear axle, Triumph Herald suspension uprights at the front, and bigger, more powerful Ford engines with Cosworth tuning. So which to choose as an exemplar for the breed? Well, you want an early car for its purity, but even better to have one with sufficient power to exploit that delectable handling. It should be a Series 3, as that version, in effect, is what Caterham still builds – for more on the 7’s production history, see our story after the end of this feature, where you’ll also learn why Caterham didn’t bother continuing with the ugly Series 4…

First, though, feast your eyes on this delectable 1969 Twin Cam SS, one of only 13 built with the Elan’s Ford-based, Lotusdeveloped 1558cc twin-cam four-cylinder, in this case modified further by Holbay with bigger valves and wilder cam profiles. It starred on Lotus’s motor show stand at Earls Court in 1969, and a couple of years later became the property of Graham Nearn, a Lotus dealer based in Surrey, just south of London. In a town called Caterham.

And that’s a huge clue as to what happened when Lotus, faced with the demise of purchase tax (which rendered kit cars little cheaper), decided to go exclusively upmarket with its Elite, Eclat and Esprit models, offloading the production rights to the 7. More of that later. Time for a drive first. No doors, so you hop in over the side, swinging back the sidescreens first, feet on the seat (a simple vinyl-trimmed cushion, fixed in place) then drop, sliding your legs forward and under the wheel. Doublejointed knees would help, but, once ensconced, you’re snug, wedged between the outer spaceframe and the transmission tunnel, the tiny wheel vertical above your lap, toy-like gearknob a handspan to its left.

Turn the key, then grope for the starter button, under the dash on the bulkhead. That twin-cam erupts with a gruff bark, and burbles at idle. A twin-cam 7 was never envisioned, Chapman having been of the belief that it wouldn’t fit until a 7 owner proved otherwise, but it feels entirely natural, at home in this roller-skate of a car, making it more of a thoroughbred: the automotive equivalent of a watch with an in-house movement.

It might have a swept volume of only 1558cc but it feels so much bigger-lunged than that. OK, so the combination of decent power and tiny weight is always going to create that illusion, but there’s more to it than statistics. The noise, for a start, a deep grumble that builds to a bellow in direct proportion to the pressure exerted by your right foot. And there’s the electrifying throttle response too, the kind that modern fuel injection just can’t replicate: twin Webers are where it’s at.

The four-speed gearbox has a brilliant shift (thanks, Ford); you snick from one ratio to the next with the tiniest, deftest flick of the wrist, grinning at the well-oiled-machine nature of it, no motion lost, just a satisfying sensation as the bolt clicks home. Then you’re straight back on the power to be treated to another kick in the back, matched by the snort and growl up ahead.

There’s 125bhp on tap, though you’d swear it’s more, and the raw acceleration figure of 0-60mph in 7.1 seconds sounds longer than it feels. But, then, sensation is always more important than figures on paper. Equally, the top speed of 110mph is irrelevant. Those billowing glassfibre front wings (the earliest 7s had alloy cycle wings) will have you airborne well before you hit Vmax.

So, yes, it feels quick, but the 7 is obviously more about the handling. And this prime example of a Lotus is about as good as it gets. There’s a live axle bumping away under your behind but it’s actually more supple than you might expect, keeping you well in touch with the road surface yet rarely bouncing you off it. And it engenders supreme adjustability through corners: apply a bit more throttle, feel your angle of attack tighten, but back off and it won’t bite you like some cars will.

The 7 is sharp, agile, yet it is rarely edgy. And you can feel absolutely everything it’s doing, especially through that tiny wheel, via which hints from your wrists translate to instant reaction at the front wheels.

This special 7 is all the more amazing because it spends so much time on display at the British Motor Museum in Gaydon, Warwickshire, where it’s on loan from Graham Nearn’s son Simon. So it doesn’t get driven hard often. But when it does, boy, can it deliver. It’s a beautifully patinated device, no trailer queen, and the only evidence of any recent restorative work is in the seat cushions, whose white piping has yet to fade to cream and match that of the seatback.

What a car. That something so simple can deliver such massive (and honest) pleasure is the purest testament to the genius of Colin Chapman. I can remember, in my early teens, when Car magazine ranked a 7 in its Top 10 cars of 1986 (turns out it was usually in there, year in, year out, along with a 911, a motley selection of Citroëns and the odd Jag), and the reason I recall it so vividly is that the car seemed such an anachronism even then – more than half its lifetime ago.

Only it wasn’t broke, so Caterham didn’t fix it. Instead, it has honed and improved the breed over the years, and there are many different versions to suit many different tastes, even today, from the three-cylinder live-axled 160 to the track-focussed 620R. If you’re in the mood for a bit of a history lesson, turn the page.


TECHNICAL DATA FILE SPECIFICATIONS 1969 Lotus 7 Twin Cam SS

Engine 1558cc four-cylinder, DOHC, twin Weber 40DCOE carburettors

Power 125bhp @ 6200rpm / DIN

Torque 116lb ft @ 4500rpm / DIN

Transmission Four-speed manual, rear-wheel drive

Steering Rack and pinion

Suspension

Front: double wishbones, coil springs, telescopic dampers, anti-roll bar

Rear: live axle, A-frame trailing links, coil springs, telescopic dampers

Brakes Discs front, drums rear

Weight 570kg

Performance

Top speed 110mph

0-60mph 7.1sec


1969 Lotus 7 Twin Cam SS - celebrating six decades
1969 Lotus 7 Twin Cam SS – celebrating six decades. Right, from top Lotus’s twin-cam seems perfectly at home here, yet such a version didn’t form part of Colin Chapman’s plan; stark interior is just perfect; instant grin when you drive it, especially when there are corners involved.

‘THAT SOMETHING SO SIMPLE CAN DELIVER SUCH MASSIVE PLEASURE IS THE PUREST TESTAMENT TO THE GENIUS OF COLIN CHAPMAN’


 

THE SEVEN STORY

From 1340cc to 310bhp in six decades – via much evolution and several changes of ownership. Words John Simister.


You’ve just read how the 7 was conceived and reached its definitive Lotus form. The twin-cam version, though, was an exotic rarity. Most Lotus 7s used pushrod Ford engines, in pre-crossflow 1340cc or five-bearing 1498cc form, then Kent crossflow guise.

That’s where the 7 was at, engine-wise, when Colin Chapman let it go. It was already semidetached from the rest of the Lotus range, sitting uneasily with smoother-looking, highertech, ‘normal’ Lotuses, and it was built and sold by a separate Lotus Components Ltd division, which also built customer racing cars. Latterly the 7 had become too expensive to build, with all those tubes and aluminium sheet, so in 1970 Lotus Components redesigned it with an enclosed tail end in glassfibre. It had a sculpted, modern look, thought the stylist, and the nose section was squared-off to match.

Nearly everyone hated the resulting Lotus 7 Series 4. Even in the forward-looking 1970s, people realised that mutton and lamb met here in a very uneasy mix, newly built-in heater or not. So once Graham Nearn’s Caterham Car Sales had sold the last of the S4s he acquired from Lotus in 1973, along with the manufacturing rights, Nearn reverted to the ‘classic’ S3 design for 1974.


1969 Lotus 7 Twin Cam SS - celebrating six decades

1969 Lotus 7 Twin Cam SS – celebrating six decades

THE NEARN ERA

Graham Nearn’s operation had already been the sole agent for the Lotus 7 since 1968, but as of 1973 the cars became, officially, the Super Seven, with a new badge featuring the Lotus triangle cleverly inverted to house the figure 7. They soon became known as the Caterham 7, though, and the name has stuck. The first Caterhams used the Lotus twin-cam engine, but supplies finally dried up in 1980.

So, via a short-lived flirtation with a Vegantune VTA twin-cam, it was back to the Kent engine, which reached its peak in 1984’s 1700cc Super Sprint, by which time a muchneeded ‘long cockpit’ chassis was available.

Also offered was a Cosworth BDR with 170bhp, powering the first Caterham to be called HPC after driving guru John Lyon’s High Performance Course – compulsory for every new customer. From 1985, buyers could specify a de Dion rear axle in place of the live one.

A MOVE TO DARTFORD

In 1987, having outgrown the original workshop at Caterham, the company moved manufacture to Dartford, Kent. A year later the brakes became all-disc and the suspension geometry was revised, setting the 7 well on the course that has made today’s super-sharp, ultrataut versions feel entirely different from the soft, flowing Lotus Sevens of the 1960s.

In 1990, a Vauxhall 2.0-litre ‘Red Top’ twincam propelled a relaunched HPC model, joined in 1992 by the first Caterham to be powered by Rover’s K-series engine – a perfect fit with the lightweight Caterham ethos. A year later, both cars could be bought fully built for the first time, along with 1994’s ill-fated Caterham 21 with a modern, full-width body which Lotus’s Elise rendered redundant. A six-speed gearbox arrived in 1996, as did the featherweight, stripped-out Superlight. With 190bhp, that became the Superlight R for 1997, followed by the even faster R500 with 230bhp.

Developments included the longer, wider SV chassis with independent rear suspension and inboard front, Honda Blackbird and Fireblade motorcycle-engined models, and an ultimate Cosworth-powered CSR version with 2.3 litres, up to 269bhp and the option of a sequential gearbox. Simon Nearn had by then taken over the firm from his father, and in 2005 he sold it to a venture capital group headed by Ansar Ali.

UNDER NEW MANAGEMENT

Caterham prospered under Ali, continuing the successful Caterham Academy learn-to-race series that moved, like the entry-level road cars, to Ford’s compact Sigma engine in 2008 as supplies of the K-series dwindled. Ali sold the business to Tony Fernandes in 2011, who created a Caterham Formula 1 team when Lotus obliged him to cease running his outfit under Team Lotus branding.

That venture failed, as did the joint project with Renault that has become the new Alpine. But Caterham’s core sports cars are as popular as ever, be they powered by a tiny, 660cc Suzuki Swift motor with just 80bhp, a 1.6-litre Ford Sigma or a 2.0-litre Ford Duratec with up to 310bhp for the 620R model. Somehow they continue to get through all the regulations, yet they remain clear descendants of the Lotus original, even if every component has changed. Caterham Cars has nothing to with the Surrey town any more, however. Since 2014 its HQ has been in Crawley, Sussex.


 

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