The name Diablo means "Devil" in Spanish (not Italian). Like Countach and many other Lamborghinis, it was designed by Italian styling master Marcello Gandini, no wonder the car has strong resemblance to its predecessor, such as slant front end, steeply raked windscreen and scissors doors. However, the final design was refined by Chrysler's studio in the USA, smoothened all sharp edges and corners, improved cooling and aerodynamics. In the end, it was changed so much that Gandini was very angry. As a revenge to Chrysler and Lamborghini, he simply adapted his original design and offered Cizeta Moroder V16T. 

However, it is undeniable that the Chrysler-refined Diablo was more beautiful and more enduring than the Cizeta. It looked pure yet aggressive, futuristic yet mature. Chrysler designers' attention to details complemented what Gandini infamous of. Most important is that it felt truly EXOTIC, which was exactly what contemporary supercars lack of. McLaren F1 and Jaguar XJ220 might look sexy, but not exotic enough. The Lamborghini was different. Its styling meant velocity, acceleration and power. Even in standstill, its appearance told you it was a 200mph supercar, no, perhaps 250mph ! if you let me name the most beautiful supercar design during the 90s, Diablo will always be the first one I think of.  

However, technology-wise, Diablo was just an extension of Countach. When the Countach was launched in the early 70s, its spaceframe chassis, aluminium body and transmission layout were rather advanced. Entered the late 80s, Porsche 959, Ferrari GTO and F40 started a supercar revolution by using lightweight construction, twin-turbo engines and space-age carbon-fiber materials. In contrast, the Diablo still rested on the laurel of Countach without any significant changes. The chassis, body and the big V12 were just evolution from the old one. And unsurprisingly, it gained more length, width and wheelbase as well as a touch more (desperately needed) cabin space. As a result, a standard Diablo tipped the scale at more than 1600kg, about 130kg heavier than the last Countach.  

Straight-line performance was never a problem to the Diablo, because its 5.7-litre V12 produced close to 500 horsepower. It was recorded 0-60mph in 4.5 second and a top speed of 202 mph - the wild claim of early Countach was finally fulfilled by its successor. At the time of writing, the Diablo still holds the record of being the fastest production car. Of course, some limited production supercars did record higher speed. 

The V12 was always the jewel of the crown. Powerful, sharp throttle response aside, it impressed most with its thundering roar, a roar that resonant your heart beat in sync with rising rev. Louder and rawer than Ferrari’s V12, the Lamborghini engine noise could hardly forgettable.  

The problem of Diablo was actually handling. Its philosophy of "big and powerful supercar" was almost old-fashion since its launch. It was too heavy, too wide, too bulky to handle. Although its supercar tires produced massive grip while its extra track aided cornering stability, it never felt as agile as a smaller supercar, or even a Porsche 911 Turbo. Poor visibility front and rear also limited driving confidence. Unless on smooth and wide racing track, the Diablo could hardly keep up with a 911 Turbo which cost less than half ! even on racing track, its brakes were not big enough to handle its weight effectively. 

During its 11-year life, Diablo evolved gradually (see article below). The SV from 1995 to 1999 was perhaps the best Diablo, thanks to the diet it underwent. The GT of 2000 was even developed into a respectable racing machine, pushing performance to the peak.  

Because of the emergence of many super-expensive supercars in the early 90s, such as Bugatti EB110, Jaguar XJ220, McLaren F1 and Ferrari F50, the Diablo was almost forgotten. Being slower, heavier, cheaper and less exclusive, the Diablo failed to recapture the fame of Countach which was regarded the world’s top supercar for many years. Admittedly, Diablo was the only product of Lamborghini so that it must be relatively cheap to build in order to sell 300 to 400 cars annually, in contrast to the aforementioned one-off exclusive. This relegated it to the "second division" supercar club whose members left only the last breed of boxer Ferrari, that was, 512TR / F512M. Undoubtedly, the Lamborghini was always rated as the best one of its kind. Since the death of F512M, the Diablo became the only mid-engined production supercar in the world. Then people could only compare it with the front-engined GTs such as 550 Maranello and Aston Vantage. Diablo’s production dropped gradually despite of a revision every 1 or 2 years. Perhaps people became more concern about drivability and comfort, perhaps the old Diablo could no longer get people excited, it had to retire in 2001. 

However, we will always remember the best things of Diablo: the exotic appearance and the thundering V12. 
 

Evolution and Derivatives

Diablo VT

Diablo SE30

The hottest Diablo in 1995 was SE30, which was the special edition for celebrating the 30 years anniversary of Lamborghini. Modifications included : 

• Use of magnessium wheels and other lighter metal, plus the carbon fiber engine cover, wing, less equipment, thinner cabin trim and racing seats so that the kerb weight is reduced by 108kg.
• Different engine components and program increases the power to 525hp.
• Owing to the enhanced weight and power, it was capable to reach 207mph top speed and took just 4.2 sec for 0-60 mph.
• Adjustable anti-roll bar suits different roads.
• Different front bumper increased cooling air channelling the front brakes, while the new engine cover reduced drag and enhanced engine cooling.
• A unique purple body paint which was not available on any previous Diablos.

Diablo SE30 Jota

Jota was the lightest yet by far the most powerful and the fastest Diablo. It weighed just 1460kg, or some 72kg lighter than a standard SE30. The V12 received a ram-air intake which eventually applied to SV also. Variable-length intake ducts, variable exhaust and race-style cams also helped it to achieve 590 hp and 448 lbft. However, it might not be completely complied with the emission regulations in EU or the US.

Italian car magazine Quattroroute tested the Jota once and recorded 207 mph. Undoubtedly, this is the fastest Diablo of all.

Diablo Roadster

Diablo SV

Bigger valves, different cams and ram-air device helped increasing power to 510 hp while less equipment and lighter seats helped reducing kerb weight to 1570kg. Thus the SV stood between the SE30 and standard Diablo in terms of power and weight. It was a lot cheaper than the SE30, and even cheaper than the standard Diablo, thanks to the short standard equipments list. Shorter final drive ratio led to the lowest top speed among all brothers, 186mph. However, with the much improved handling, who cares about the nonsense top speed ? 

Diablo SV was upgraded in early 98 with improved engine. The V12 gained a two-stage variable valve timing at inlet valves. Power increased to 530hp while torque was up from 428lbft to 450lbft. Moreover, the VVT enabled more healthy spread of torque at lower rpm, this explained why Autocar recorded incredible improvement in in-gear acceleration. 

Other improvement included bigger brake discs - 355mm up front ; 335mm at the rear. As a result, bigger 18-inch wheels were employed to accommodate the brakes. Besides, ABS and airbag were eventually available in a Lambo ! 

The new SV might be even faster than SE30. Factory figure claimed 208mph, 1 mph faster than that special edition. But what impressed me is not the already useless top speed, it is the sharper handling that appeared since the first SV, and the faster acceleration plus the drivability in the new version that keep me faithful with the big Lambo. Lamborghini succeeded in rationalise the short-coming of Diablo, while still preserving its exotic image. 

Diablo '99

Again the whole Diablo family received some minor modifications. Although engine and performance remained unchanged, there was a completely redesigned interior which featured a simpler instrument for easier reading. Passenger's airbag was added near the new glove box. The only mechanical change was the addition of electronic adjustable damping. 

All Diablo, including the standard Diablo, VT and Roadster became sharing SV's 530 hp variable valve timing engine. For SV, the "SV" sweeping graphic which used to be feature at the side was deleted. 

However, the most eye-catching new feature was undoubtedly the fix rectangular headlamps which recessed in the front end, replacing the memorable pop-up lamps. These lamps, bought from Nissan 300ZX, does not look as stylish as before but they are part of the company's effort to cut Diablo's production cost. 

Diablo GT

From its outer look, you’ll know its racing origin. The nose had a large air intake drawing air to oil cooler, which was repositioned from engine bay to the front for higher cooling efficiency and better weight distribution. Hot air left the car from a new air scoop on the bonnet. Brake’s cooling intakes were also enlarged. Black carbon fiber lip spoiler, side skirts and rear diffuser added downforce. Quad exhausts were replaced by twin centrally mounted exhaust. Because ram-air intake blocked rear vision, it used camera instead of rear mirror. Driver could see what’s happening behind the car by looking at the LCD monitor in the center console. 

The GT weighed 1490kg in dry, 80kg lighter than SV. All body panels, excluding aluminium doors and steel roof, were made of carbon fiber. In the engine compartment, intake manifolds were made of magnesium, further reduced weight distribution to 40:60. Besides, Lamborghini also widened the front track by 110mm, revised front suspension geometry, stiffened the springs and softened the dampers, the result was more high speed stability and quicker turn-in at low speed. The new suspension improved handling very much, making it remarkably balanced at cornering limit. The steering feel was terrific, unexpectedly light and accurate, although the car still felt big to handle. Oversteer or understeer can be controlled beautifully by throttle. The GT was the best handling Diablo. What a pity it was a one-off production with only 80 units built. 

Diablo 6.0 VT

The V12 was bored out to 6.0 litres, in addition to titanium connecting rods (from the GT), lighter crankshaft, individual coil-on-plug ignition and two-stage variable exhaust (for complying noise regulation without losing power), it pumped out 550 hp and 458 lbft. Compare with the GT, it didn’t have the ram-air intake on the roof (hence saving a rear-vision camera) and hotter cam timing.  

Like the GT, the 6.0 VT got wider tracks front and rear. In particular, there was 60 mm added to the front to improve turn-in response as well as stability. However, it didn’t steer as sharp as the lightweight SV, especially the viscous-coupling 4-wheel drive introducing quite an amount of understeer approaching the limit. In terms of performance, it was also slower than the SV, blamed to nearly 200 kg of extra weight it carried. 

Interior was trimmed with carbon-fiber panel while position of pedals and gear lever were also improved a little bit.