Guide: The 70s Brightest Failure - a Historical & Technical Appraisal of the Lamborghini Silhouette P300
Background
Lamborghini’s first attempt at producing a high volume junior model, the Urraco, had been a commercial failure. Introduced at the Turin Motor Show in November 1970, it was two years late going into production and sales figures barely hit 10% of the firm’s target.
Tooling and factory expansion for the new model had come at considerable expense. Unfortunately, Lamborghini’s problems were further compounded by delays to the Countach and a change of company ownership. Ferruccio Lamborghini had left the firm in 1974 and the new owners, Swiss industrialists Georges-Henri Rossetti and Rene Leimer, took the firm down a path of inexorable decline.
Internal problems were made worse by factors outside the firm’s control. Ferruccio Lamborghini had departed in the midst of a two-year energy crisis that saw demand for high performance cars evaporate practically overnight.
Amid this strife, at the Geneva Motor Show in March 1976, Lamborghini launched their first new model for several years.
Based on proven Urraco P300 underpinnings, in an ideal world, the gorgeous two-seat targa-topped Silhouette would have sold by the bucket load. However, buyers for Lamborghini’s first production Spider were thin on the ground; the firm’s problems were well documented and customers opted for the Ferrari 308 and Porsche 911 instead.
Technically inferior the opposition may have been, but perception mattered; these companies would still be around in a few months to supply the parts needed to keep their cars on the road.
Internally designated Tipo P118, the Silhouette took advantage of suspension, wheel and tyre technology that had been introduced since the Urraco was launched.
Named after the new-for-1976 Group 5 Silhouette formula devised for GT racing cars, this latest model would slot into a line-up that comprised the Urraco P300, Countach LP400 and Series 3 Espada.
Chassis
As it would be losing its central roof panel the Urraco’s steel monocoque chassis was suitably reinforced to eliminate flex. In the transition to Silhoutte trim, a strengthened roll-over hoop was also added to comply with the latest regulations for open top vehicles.
Important changes were made to the suspension to accommodate Campagnolo’s new Teledial wheels and the latest generation Pirelli P7 low profile tyres. At the time, wider versions of these rims were being fitted to the factory built Countach Speciale hot rods as delivered to Walter Wolf and a couple of other high rolling customers.
The Silhouette would be the first production Lamborghini to be fitted with this style of wheel and the suspension geometry was modified accordingly. Front suspension was still via MacPherson struts with lower A-arms, but the back was now equipped with Chapman struts, reversed lower A-arms and trailing arms.
Coil springs and telescopic shocks were fitted to each corner along with anti-roll bars at either end.
The Urraco’s twin circuit hydraulic brake system was plumbed straight in along with unchanged 278mm ventilated Girling discs.
Designed specifically for Pirelli’s P7 tyres, the cast magnesium Teledial rims had a 15-inch diameter. They measured 8-inches wide at the front and 11-inches wide at the rear. For comparison, Urracos ran 14 x 7.5-inch wheels shod with traditional Michelin XWX rubber.
The new wheels, tyres and suspension saw track expand by 34mm at the front and 62mm at the rear.
As usual, an 80-litre fuel tank was housed in the engine bay.
Engine / Gearbox
Lamborghini’s Paolo Stanzani-designed all-alloy 90° V8 from the Urraco P300 was used for the Silhouette. This was the reworked and enlarged version of Stanzani’s original engine which significantly now featured dual overhead camshafts.
Displacement was 2995cc thanks to a bore and stroke of 86mm and 64.5mm respectively.
Compression was set at 10:1.1 and four Weber 40 DCNF downdraught carburettors were installed. Ignition was via two Marelli coils and a single Marelli distributor.
Peak output was 260bhp at 7500rpm and 195lb-ft at 3500rpm.
Transmission was via Lamborghini’s own five-speed manual gearbox, a single dry-plate clutch and in-house-made differential.
Bodywork
Carrozzeria Bertone were tasked with transforming the Urraco into a targa-topped two-seater.
They produced arguably the best-looking junior supercar of the seventies.
Although clearly derived from the Urraco, the Silhouette was better proportioned and more aggressive.
Squared and flared wheelarches covered the Teledial wheels. At the front, the arches were integrated with a deep chin spoiler that housed supplementary driving lights and a radiator intake.
The Urraco’s nose profile, retractable headlights and front bumper were carried over, however, the vented front lid was replaced with a solid panel.
Doors were also sourced from the Urraco, but new windows swept back into the body-coloured roll-over bar. Behind this was a grey engine cover that housed a cooling scoop on each sail panel. The engine cover was flattened in the centre to provide excellent visibility through the vertical rear windscreen.
The bootlid, tail fascia and rear lights came from the Urraco. For improved safety protection, bigger back bumpers were installed.
Aside from the door catches, all chrome was replaced with anodised black metal.
Overall, the Silhouette was 35mm longer, 140mm wider and 40mm lower than the Urraco.
Interior
A new dashboard was more sensibly laid out than before and once again upholstered in mouse-hair-type alcantara.
Behind the four-spoke Urraco steering wheel was a binnacle that housed all major instrumentation. Large read outs for road and engine speed were complemented by smaller gauges for fuel level, oil pressure, oil temperature, water temperature and battery amps.
An assortment of switches were contained in a central control panel along with the stereo and clock.
Like the Urraco, ventilation controls and outlets were mounted on a console that connected the dash with the transmission tunnel.
New bucket seats were fitted. They featured a vertical stripe and came upholstered in fabric as standard or leather as a cost option. As the rear seats had been removed, there was plenty of space for the targa top and an assortment of luggage.
Weight / Performance
The extra weight from the chassis bracing and beefed up suspension was more than offset by the pared down interior. As a result, the Silhouette tipped the scales at 1240kg which was 60kg less than the three-litre Urraco.
Weight distribution was 45/55 front to rear.
Top speed was quoted as 161mph and 0-62mph took 6.2 seconds.
Production
The first Silhouette was delivered in September 1976, six months after the model had debuted at the Geneva Motor Show.
However, like the Urraco, the Silhouette was never homologated for sale in the USA, so only a handful of grey market cars made their way across the Atlantic.
By the time Lamborghini filed for bankruptcy in October 1978, just 52 Silhouettes had been completed, ten of which were right-hand drive.
Lamborghini had been given a lifeline in 1976 when BMW commissioned the firm to develop and build their M1 supercar. However, Rossetti and Leimer took the BMW cash and inexplicably spent most of it to develop the Cheetah military fast response vehicle.
When BMW pulled out, Rossetti and Leimer were unable to find a buyer for the firm and Automobili Lamborghini was declared bankrupt by the Italian courts.
A replacement for the Silhouette finally appeared in 1981 when Lamborghini’s new owners launched the Jalpa.
Text copyright: Supercar Nostalgia
Photo copyright: Lamborghini - https://www.lamborghini.com
