When Lotus sprinkled their own special brand of stardust over the unassuming Vauxhall Carlton, all hell broke loose.

Once they found out its top speed of nearly 180mph, some members of the press, police and even Parliament called for the car to be banned.

This is the story of the executive saloon turned supercar.

Lotus was no stranger to turning ordinary road cars into something special.

But as outstanding as their tuned ‘60s Cortina and ‘70s Sunbeam were, they proved to be mere tasters for the main event, the earth-shatteringly spectacular Vauxhall Lotus Carlton of 1990.

Here was a car that could more than match a Porsche 911 or a Ferrari 348 for speed, but could also seat four in comfort and carry a fortnight’s worth of luggage.

Even though there were already sports cars on the road that could achieve outrageous top speeds, the fact that this was a humble Vauxhall, a recognisable family saloon, was too much for some.

Before anyone had even taken delivery of Lotus Type 104, the Daily Mail wailed that it was too fast and should be banned, aided and abetted by the Association of Chief Police Officers, who described it as “an outrageous invitation to speed”.

Questions were raised in Parliament, and even Bob Murray, editor of the respected Autocar magazine, doubted the wisdom of allowing a car that could reach speeds of up to 180mph on the road.

He took the view that the car’s top speed should be limited, though the 155mph the Germans had begun to adopt was still too fast for British roads…

“Nobody buying this car could possibly argue he either needs or will be able to use a top whack which is claimed to be around 180 mph,” argued Murray.

Vauxhall’s owner General Motors, and especially Lotus, were unmoved.

Lotus Carlton engineering

General Motors had bought Lotus in 1986, and Mike Kimberley, boss of the Norfolk firm, immediately spotted an opportunity to give the Vauxhall range an image boost.

To start with, he considered giving the top-of-the-range Vauxhall Senator the Lotus treatment, with a number of concepts and renderings drawn up.

But GM Europe had its own plans for the Senator, and attention switched to the slightly smaller Carlton, sold as the Opel Omega in Europe.

With GM on board, work got underway on the already impressive 3.0-litre, six-cylinder Carlton GSi 24v, which Lotus enlarged to 3,615cc by increasing the stroke.

Kimberley wanted supercar performance to push the envelope of what a family saloon could be, which meant bolting on a pair of small Garrett T25 turbos among a host of other engine modifications.

They included a stiffer block to deal with the extra power and torque, new Mahle pistons, connecting rods, and crankshaft, a reinforced cylinder block, a new induction system, cooling manifold and throttle bodies, better cooler and better oil flow.

Other changes included a beefed up clutch, a ZF six-speed gearbox designed for the Corvette ZR1, and rear differential from the Holden commodore V8.

Stopping the massive 17in wheels, shod with unique Goodyear Eagle tyres, was a braking system designed by AP Racing.

Four pot racing callipers at the front, originally designed for Le Mans, on 330mm vented discs, are joined by twin piston callipers on 300mm vented discs at the rear, while the standard GM/Bosch anti-lock system is retained.

There was also speed-sensitive power steering and self-levelling suspension from the Senator.

Available only in Imperial Green, the Lotus Carlton was clothed in a purpose-built body kit featuring a rear spoiler, side skirts, and two huge cooling ducts in the front apron.

Made in Norfolk

Kimberley secured permission to build the car at Lotus’s plant at Hethel, Norfolk, with right hand drive Carltons and left hand drive Omegas shipped from Opel’s plant at Russelsheim starting in 1990.

These were fully completed GSi models, so each car had to be stripped down and fully rebuilt in the firm’s Factory 3, with the standard engine sent back to Opel.

It wasn’t the most efficient way of producing a car…

There were 1000 new components in the car, and each engine – comprising all new parts – was handbuilt by one of five Lotus engine builders.

Eleven prototypes were manufactured at Lotus and put through a rigorous testing regime, with the firm’s elite test drivers unleashing the awesome power of a machine that would redefine saloon car motoring.

Lotus had originally wanted to extra 100bhp per litre from the engine, but in the end delivered 377bhp at 5200rpm, and a huge 419lb ft of torque at 4200rpm – Ferrari and Lamborghini levels of grunt.

An impressive 75 per cent of that torque was available from just 2,000rpm, while it was rumoured that even at idle, the Lotus Carlton produces more torque than Vauxhall’s 24-valve Carlton at full revs.

So what did all this add up to in performance terms?

Lotus’s test drivers covered to 0-60mph sprint in just 5.2 seconds, 0-100mph in 11.5 seconds, and saw top speeds of 180mph with a following wind.

It was the fastest car ever built in Britain, quicker than the Aston Martin Vantage at 170mph.

Not even the benchmark BMW M5 could compete, but it was also these figures that sparked concerns among road safety campaigners.

Maybe that’s why Vauxhall decided to offer a day of high intensive driver training with every car sold, included in the asking price, run in conjunction with the Institute of Advanced Motorists and the Jim Russell Driving School.

The course comprised lectures in the theory of performance motoring, followed by practical experience at the wheel of the driving school’s own Lotus Carlton, all conducted in the safety of the Donington track.

It wasn’t compulsory, and Autocar’s first road test described a chassis that “tames the fury so effectively that you don’t need to be Ayrton Senna to drive it well”.

“This is the only car we’ve ever recorded a 140-160mph time for, yet such is its overtaking ability and braking power that it’s incredibly safe.”

In the wet though, the combination of huge rear tyres, rear wheel drive and mighty turbo boost could cause the rear end to step out in the hands of the unwary.

“In the wet the choice was stark; leave the Carlton at home or tiptoe everywhere.”

Lotus Carlton: a road tester’s delight

While the naysayers decried the car’s speed, most of the motoring press couldn’t wait to get their hands on the new £48,000 fire-breathing super-saloon.

By the time Autosport tested the car after the Geneva launch, Vauxhall was already getting twitchy about reports of the car’s top speed. Indeed, the press information issued to road testers ignored it entirely.

Vauxhall preferred to focus on other factors instead, like the 0-60-0 time of 8.5 seconds: the time it takes to go from 0-60mph and back to a standstill.

It will stop from 60mph in half the distance of the average family runabout.

Autosport wrote that the Lotus Carlton, a “remarkable machine”, “really comes alive on A and B roads where its explosive acceleration, responsive handling and sheer grip are waiting to be unleashed”.

“It has the power, the acceleration and handling of a mid-engined supercar and none of the drawbacks. It will seat four in supreme comfort, is far easier to drive than the performance figures suggest and asks the driver to make no compromises.

“It takes 150 hours to create a Lotus Carlton, to turn a mass produced Vauxhall into a hand finished Ferrari frightener.”

The magazine’s only quibble was with the gearbox, which “verges on agricultural” compared with Alpina’s 5-series based B10 Bi-Turbo, which develops almost as much power and torque and “uses a delightful new Getrag 5-speeder”.

The Alpina, though, was £10,000 more expensive and only available in left hand drive.

“A Lotus from Luton might not have the cachet of a BMW or a Porsche – but there’s a heck of a lot else going for it,” Autosport concluded.

What Car? said the Lotus “looks like a prop from sci-fi film The Terminator, evil and gruesome, ready to devour anything in its path through those two huge nostril-like cooling ducts in the front apron.

“Initially there’s just a gentle rumble from under the bonnet, but as the revs rise there’s an altogether more menacing growl accompanied by the odd whistle and scream from the twin turbochargers.

“And boy, does this car go; floor the throttle at 50mph in third and you’ll reach Britain’s legal speed limit in under three seconds, which is enough to leave Porsche 911 Carreras and Ferrari 348s trembling in your wake.”

Also a joyrider’s delight

It wasn’t long before thieves and joyriders cottoned on to the awesome power of the Lotus Carlton, with no police car on the road able to keep pace.

One particular car, registered 40 RA, became an almost mythical beast after it was stolen from a home in the West Midlands in November 1993.

For months, it roamed the streets in the hands of thieves who used it in late-night ram raids to steal thousands of pounds worth of cigarettes and alcohol.

West Midlands Police admitted that they “simply haven’t been able to get near the thing and it looks unlikely that we ever will”.

Vauxhall originally planned to sell 440 cars in the UK, through 17 specially chosen dealers, with a further 660 available as Lotus Omegas in left hand drive.

In the event, the recession of the late 80s and early 90s hindered sales, and only 320 Carltons and 630 Omegas were produced.

This, of course, makes them even more rare today, although a fairly large percentage survive in the UK, with 181 either on the road or SORN’d according to How Many Left.

At the time of writing, there is just one for sale in this country, a 73,000 mile, 1991 example with an asking price of £90,000.

Over time, the Carlton’s 377bhp and 419lb ft of torque has been overtaken by more modern super-saloons.

For example, the latest Audi RS6 kicks out a ludicrous 592bhp, with 590lb ft of torque, and the BMW M5 Competition an even more massive 617bhp. They can both beat the Lotus Carlton to 60mph with ease.

But at the time, the Lotus had no real competitors. It was the only four-door car on the planet with supercar performance.

Autocar summed it up thus: “Imagine that you are drifting along at 3000rpm in third gear on a straight piece of track. If you floored the throttle now, gripped the wheel, held it straight, and kept your head erect against the strong rearward force, you’d be doing 100mph now. That’s memorable.”