Lamborghini Diablo VT Roadster: monarch of the glen

By Ross Alkureishi

| 11 Feb 2025

Classic & Sports Car – Lamborghini Diablo VT Roadster: Monarch of the Glen

Never the most discreet of powerplants, Giotto Bizzarrini’s tour de force is currently doing its best to turn the other residents of The Killin Hotel into early morning curtain-twitchers.

The sight that greets them is otherworldly, and a monstrous apparition of all that’s expected of a mid-1990s supercar: menacing, oversized presence; front-hinged scissor doors; a profusion of wings and air intakes; and truly mammoth amounts of rubber.

As the wedge-shaped gap above this machine’s rear engine lid indicates, however, this is no ‘ordinary’ Lamborghini Diablo.

It’s a VT Roadster – well, more of a targa than a roadster, recalling the V8 Silhouette and Jalpa, and the first production car in three decades to liberate fully the 12-cylinder engine’s sonorous voice.

The Lamborghini Diablo VT Roadster’s Bizzarrini-designed V12 engine makes 492bhp

Whipping off the carbonfibre roof panel is a breeze – it weighs just 7kg. Locating it on top of the engine cover requires a little more care.

Once it’s in place, you undertake that unique Lamborghini entrance limbo then activate an electro-pneumatic system that employs two pivots to securely clamp the panel.

“It’s such a satisfying design,” says Carlo McCrindle, whose firm, Top Gear Specialist Cars, provided this Roadster.

“Why Lamborghini didn’t use it on the Murciélago is a mystery.”

The Diablo has traditionally been perceived as a particularly brutal piece of kit, but the cabin has an unexpectedly luxurious feel, with a profusion of the best leathers, thick carpets, air-con and electric windows; even the precision cut of the glass edges on the side windows scream class.

The steering column and seats are adjustable, with only the slightly sidesaddle driving position – caused by the footwell intrusion and the subsequent offset pedal box – and impinged rear view hinting at supercar compromise.

The Lamborghini Diablo’s huge performance is much more accessible in four-wheel-drive VT Roadster guise

All very refined and not at all what you expect.

A quick blip of the throttle instantly shatters any illusions of gentility, as the exhaust note thunders with intent around this ancient village.

Such is the cacophony, I’m sure a few troubled souls have been stirred up in Finlarig Castle – the only one in Scotland with a beheading pit.

It’s probably time to leave before we become personae non grata for our return to the hotel later in the day.

Upon pulling out on to the high street it’s immediately clear, at low speeds at least, that the Roadster is a remarkably civilised beast.

The clutch is surprisingly light and obliging, plus the five-speed dogleg gearbox – a new design for the Diablo, to incorporate the transfer box for this four-wheel-drive version – shifts easily between cogs with satisfyingly mechanical resistance.

There are clear links to the Lamborghini Countach in the Diablo VT Roadster’s cab-forward lines

The power-assisted steering is weighted to match your speed, so it’s easy even when manoeuvring – which is not something that could be said of the original two-wheel-drive cars.

Unveiled in Monte Carlo in January 1990, and named Diablo after a particularly fierce 19th-century fighting bull, the Tipo 132 couldn’t afford to be anything other than spectacular in the extreme.

After all, it had to follow in the trailblazing path of its Countach predecessor.

Work began in early 1986, with the first prototype appearing three years later.

Lamborghini toyed with four-wheel drive at the development stage, but ditched the crude mechanical system due to reliability issues.

Instead, traditional rear-wheel drive powered it to the title of Lamborghini’s first series-production car to top 200mph.

It took three decades for Lamborghini to build a production V12 roadster

Couple that emotive performance milestone with scintillating styling by Marcello Gandini – albeit somewhat softened by parent company Chrysler – plus a name that translated far and wide as ‘devil’, and its arrival caused quite a stir.

Under that dramatic skin, its spaceframe chassis was an evolution of the Countach’s construction, but featuring welded square tubes that simplified production and were 30% stiffer than the round-tube frame in torsion.

Crumple zones were integrated front and rear, and the cockpit safety cell was constructed from high-strength steel.

In addition, tougher alloys for the doors and the use of carbonfibre composites – for the central tunnel and body panels – worked together to improve safety.

The engineers at Sant’Agata fettled the ageing V12 to such an extent that it acquired a new type number, 521.

Bore and stroke were increased to 87 x 80mm, the compression ratio upped to 10:1 and capacity to 5707cc, with electronic fuel injection – as introduced on the later Federal-spec Countachs – and twin catalytic converters to keep a check on emissions.

‘A blip of the Lamborghini Diablo VT Roadster’s throttle shatters any illusions of gentility as the exhaust thunders with intent’

Still mounted longitudinally in the middle of the car, the V12’s aimed-for power hike to 460bhp was blitzed; instead, the stock car hit 492bhp at 7000rpm, with torque peaking at a thumping 428lb ft at 5200rpm – the latter a phenomenal 55% boost over the engine’s previous incarnation.

“It’s now perceived as a definitive 1990s supercar,” says Carlo as we head west on the A85 towards Crianlarich, “but the early ones didn’t have a good image.”

A lack of power assistance meant the steering was ponderously heavy at low speeds, plus redesigned coil-sprung double-wishbone suspension remained somewhat underdeveloped.

“The back end would snap, and you had to be very good to catch it,” adds Carlo.

It took a further three years of engineering before being rectified to a sensible degree.

At the time, perceptions of supercars allowed it to get away with being viewed as flawed, but the McLaren F1 soon arrived to show that they didn’t have to be so.

The Lamborghini Diablo VT Roadster’s pace is mighty

Ahead the road opens up, but the surface is still fairly damp and you are conscious of having so much torque available.

“That all changed with the VT,” continues Carlo. “In a standard Diablo you’d be a bit wary in these conditions, but not in this.”

That is all the encouragement I need to nail the accelerator.

There’s no delay for carburettors to come on song, the fuel-injection providing instant, all-consuming surge that pulverises the senses.

The brain is still registering the thought ‘Hell’s bells, this is fast’, yet my foot still has a distance to travel.

This is barely concealed rage in automotive form, the loss of the roof giving unimpeded access to its savage soundtrack.

We’ve hardly started our journey and already it’s obvious that no one really needs a supercar such as this, but if you have the means, and you’re serious about your petroleum fixation, then it’s surely your duty to have one.

The Lamborghini Diablo VT Roadster’s front-hinged scissor doors add to the drama

Gearshifts take some getting used to, because the in-house transmission has incredible gearing: 65mph in first; 98mph in second; 133mph in third; 169mph in fourth; and 202mph flat-out in top.

The polished gate and short, progressive throws – on all except the dogleg bottom ratio – ensure positive engagements, but what to use?

For the following 35 minutes, we dance with this beguiling devil; accelerating fiercely, shifting predominantly between second and third then making use of the equally brutal four-pot Brembo calipers with ventilated and cross-drilled discs to treat our internal organs to violent, equilibrium-resetting halts.

In next to no time we’ve powered around the hairpin to start the ascent to Rannoch Moor.

With bloodstream already saturated with adrenalin, we pull into a lay-by for a breather and the calming effect of a cuppa at a tea hut.

Parked and perched seemingly on the edge of the world, the Lamborghini’s lines are a paradox: extreme, yet at the same time smoother than those of the Countach.

The Lamborghini Diablo VT Roadster’s airy cabin

There’s a strong visual connection between Gandini’s brilliant duo, thanks to the short nose/long tail combination, but the later car lacks the original’s handsome angularity.

With roof panel in place, the VT looks uncomfortably cab-forward, but stowing the lid redresses this imbalance.

At launch, the Diablo was criticised for its size and heft, yet by modern supercar standards it’s average at worst.

The Roadster is said to be even stiffer than the closed version, which explains the complete lack of scuttle shake.

The frame is reinforced in the A-pillars, sills and across the rear of the cockpit, with an integrated roll-over bar.

Many panels – and the windscreen – are unique to the model, including engine cover, upper and lower air intakes, doors and rear bumper.

Is it pretty? Who cares? The Diablo’s excessive silhouette is all about aggressive purpose.

The Lamborghini Diablo VT Roadster spears through Scotland’s glorious Highlands

It wasn’t the company’s first attempt at an open-top V12 – Bertone’s dead-end Miura Roadster and the odd one-off appeared – but while rivals mined a rich seam in North America, Lamborghini went without.

We set off again, now comfortable enough with the vivid pace to take in some of our beautiful surroundings.

Up here you take your chances weather-wise, but we’re fortunate enough to see the clouds part and brilliant sunshine floods the cabin.

The Diablo devours the straights of Rannoch Moor with ravenous pleasure.

The sun’s rays highlight the deep oranges of the wintry vegetation, and bounce off the myriad lochs, lochans, peat bogs and streams that illuminate this wilderness; there’s something perverse about traversing this enlightened landscape in a car named Diablo, emitting a soundtrack forged by his minions.

No such worries in Glen Coe, scene of massacres and bloodshed through the ages.

Formed from the remains of a supervolcano that erupted, the resultant Caldera – Spanish for cauldron – formation is foreboding even at the height of summer.

The Lamborghini Diablo VT Roadster’s carbonfibre roof panel is stored on top of the engine cover

Up towards the northern edge on Aonach Eagach lies the Devil’s Staircase, an old military route given its name by the soldiers building roads under General Wade, because Satan was said to put in an appearance to claim his own.

Find yourself isolated up here and the environment can change in a flash, but there is little danger today: horsepower has come a long way in the intervening centuries and all 492 of the Lamborghini’s propel us through.

Just after Ballachulish we branch off on the A828 and loop round to follow the West Coast tourist route south, encountering only the remnants of the high season’s motorhome invasion.

The brooding claustrophobia of the glens is suddenly released as the VT spears along this open coastal road.

After the crossing at Loch Creran, the main road is left behind in favour of one of this area’s best-kept secrets: a lochside route, sparingly used by locals and the odd Forestry Commission worker.

It’s an undulating rollercoaster that runs along the eastern section through the Barcaldine Forest.

Here the Roadster is in its element. The steering is inspiring, but the phenomenal level of traction takes your breath away, along with the barrage of noise resonating through the trees.

The Lamborghini Diablo VT Roadster’s vast 335/35 ZR17 rear tyres give superb traction

The suspension has anti-dive and anti-squat geometry and, coupled with the VT of the title – which stands for Viscous Traction – it helps the Diablo to redefine the rules of the road.

No longer are corners taken slow in/fast out, but fast in/even faster out.

Once the preserve of fire-breathing rally machines and their roadgoing brethren, four-wheel drive was brought to the supercar world by Lamborghini.

“It transformed the car’s drivability by taming the power,” explains Carlo. “You’d need to be a lunatic to get to its limits on a public road.”

The system, developed in conjunction with Steyr-Daimler-Puch, functions via a centre differential with a viscous coupling between front and rear axles.

It’s pretty much rear-wheel drive most of the time, with up to 29% of the power sent to the front if traction is lost.

Lochs pass by in a blur as the Lamborghini Diablo VT Roadster makes rapid progress

This technology, coupled with the open top, didn’t come cheap: at launch in ’93 a VT cost £162,000, with its Roadster sibling coming in at £175,000, making it the most expensive model in the range.

That’s £27k more than the rear-drive cars and a full £50k ahead of the stripped-out SV, which became the ‘entry level’ Diablo.

After numerous lochside runs, Carlo takes the controls a little further on at Inverlochy and is soon pushing the car along at a pulsating rhythm.

The final journey back to Killin is a mesmerising drive on deserted asphalt.

The Diablo handles each attack without a hint of pendulum effect and with only reasonable air ingress into the cabin – but what it must be like at 200mph-plus is anyone’s guess.

Back at the hotel, with dinner out of the way, we feverishly retrace the day’s exertions over a couple of nips of Scotch.

The Lamborghini Diablo VT Roadster caused a stir at the hotel

I retire to bed but can’t sleep. As soon as I close my eyes, I’m suddenly transported back to the glen, attacking every crest and corner in my mind’s eye, yet still barely uncovering the Diablo’s abilities.

Wilder and more track-focused cars were to follow – as did a facelifted Roadster, with more power and faired-in headlights replacing the pop-up pods – but that glorious open-top symphony means it’s too late for me.

In my dreams, I’ve already sold my soul to this particular devil.

Images: Malcolm Griffiths

Thanks to: Carlo McCrindle, Top Gear Specialist Cars; The Killin Hotel

This was first in our April 2013 magazine; all information was correct at the date of original publication

Giotto Bizzarrini’s V12: timeless jewel

The Lamborghini Diablo VT Roadster’s V12 has even more drama, with full access to the noise

If you require a masterpiece, employ a master.

Lamborghini did just that when he commissioned freelancer Giotto Bizzarrini – of Alfa Romeo and Ferrari fame – to build a new engine.

Based on similar lines to his earlier, abandoned 1.5-litre F1 V12, the oversquare 3.5-litre unit had twin overhead cams and was more advanced than Ferrari’s then-current production engines.

From traditional placement in the GT cars to transverse-mid installation in the Miura then longitudinale posteriore in the subsequent Countach, Diablo and Murciélago, it has proven its versatility and adaptability in a wide range of models.

Capacity and power output has grown from 3.5 litres and 300bhp in the original 350GT to 6.5 litres and an incredible 670bhp in its final Murciélago 670-4 SuperVeloce incarnation.

Bizzarrini’s association with the firm may have ended in 1963, but his legacy continued until 2010, thanks to this magnificent motor.

Factfile

Lamborghini Diablo VT Roadster

Sold/number built 1995-2000/300 (est)
Construction multi-tubular steel spaceframe chassis, aluminium and composite panels
Engine all-alloy, dohc-per-bank 5707cc 60° V12, with Lamborghini LIE engine-control system and electronic fuel injection
Max power 492bhp @ 7000rpm
Max torque 428lb ft @ 5200rpm
Transmission five-speed ZF manual, 4WD via a centre differential
Suspension independent, by double wishbones, coil springs, adaptive telescopic dampers, anti-roll bar f/r
Steering power-assisted rack and pinion
Brakes ventilated and cross-drilled 13in (330mm) front, 12¼in (310mm) rear discs, with servo
Length 14ft 8in (4470mm)
Width 6ft 8in (2040mm)
Height 3ft 8in (1115mm)
Wheelbase 8ft 8in (2650mm)
Weight 3582lb (1625kg)
Mpg 12
0-60mph 3.9 secs
Top speed 202mph
Price new £175,000*