Lamborghini V12 engine

Lamborghini V12
From left to right: Giotto Bizzarrini, Ferruccio Lamborghini and Gian Paolo Dallara at Sant'Agata Bolognese in 1963, with a Lamborghini V12 engine prototype.
Overview
Manufacturer	Lamborghini
Production	1963-2011
Combustion chamber
Configuration	60° V12 petrol engine
Displacement	3.5: 3,465 cc (211.4 cu in), 3.9: 3,929 cc (239.8 cu in), 4.8: 4,754 cc (290.1 cu in), 5.2: 5,167 cc (315.3 cu in), 5.7: 5,707 cc (348.3 cu in), 6.0: 5,992 cc (365.7 cu in), 6.2: 6,192 cc (377.9 cu in), 6.5: 6,498 cc (396.5 cu in)
Cylinder bore	3.5: 77.0 mm (3.03 in) 6.2: 87.0 mm (3.43 in) 6.5: 95.0 mm (3.74 in)
Piston stroke	3.5: 62.0 mm (2.44 in) 6.2: 86.8 mm (3.42 in) 6.5: 76.4 mm (3.01 in)
Cylinder block alloy	Cast aluminium alloy
Cylinder head alloy	Cast aluminium alloy
Valvetrain	double overhead camshaft, 3.5/4.0/4.8: 2-valves per cyl, 5.2/5.7/6.0/6.2/6.5: 4-valves per cyl
Compression ratio	6.2: 11.6:1 6.5: 11.8:1
Combustion
Fuel system	3.5/3.9/4.8/5.2: 6 Weber carburettors, 5.7/6.0/6.2/6.5: electronic multi-point sequential fuel injection
Fuel type	Petrol/Gasoline
Oil system	3.5/3.9: wet sump, 6.2/6.5: dry sump
Cooling system	Water-cooled
Output
Power output	3.5: 273.7 PS (201.3 kW; 270.0 bhp) 6.2: 580 PS (427 kW; 572 bhp) @ 7,500 rpm 6.5: 640 PS (471 kW; 631 bhp) @ 7,500 rpm
Specific power	3.5: 79 PS (58.1 kW; 77.9 bhp) per litre 6.2: 94.4 PS (69.4 kW; 93.1 bhp) per litre 6.5: 98.6 PS (72.5 kW; 97.3 bhp) per litre
Torque output	6.2: 650 N·m (479 lbf·ft) @ 5,500 rpm 6.5: 660 N·m (487 lbf·ft) @ 5,200 rpm
Dimensions
Dry weight	253 kg (6.5 litres)
Chronology
Successor	Lamborghini V12 L539

The Lamborghini V12 refers to the flagship V12 engine used by Lamborghini. Lamborghini have had two generations of V12 engines through their history, both of which were developed in-house. The first-generation Lamborghini V12 was a sixty degree (60°) V12 petrol engine designed by Lamborghini, and was the first internal combustion engine ever produced by the firm.

It first entered production in 1963 as a 3.5 litre displacing 3,465 cubic centimetres (211.4 cu in) fitted on Lamborghini's first car, the Lamborghini 350GT. The engine remained in use for almost fifty years, the final version, a 6.5 litre, installed in the Lamborghini Murciélago. Lamborghini discontinued their first-generation V12 after the Murcielago, opting for a brand-new V12 that first saw use on the Lamborghini Aventador.

When Ferruccio Lamborghini set out to compete with Ferrari, he contracted Giotto Bizzarrini to design the engine for his car and, according to some accounts, paid him a bonus for every horsepower over what Ferrari's V12 could produce. The finished 3.5-litre (214 cu in) V12, with minor improvements, went on to become the 6.5 litre powering the Lamborghini Murciélago LP 640, and completed its service for Lamborghini with the final version of the Murciélago, the Murciélago LP 670-4 SuperVeloce.

The engine was designed from the start to be a quad cam 60 degree V12 - as an intentional snub to Ferrari's single overhead camshaft per-bank design. When the 3,464-cubic-centimetre (211.4 cu in) prototype was tested in 1963, it was able to produce 370 brake horsepower (276 kW; 375 PS) at 9,000 revolutions per minute (rpm), or almost 107 brake horsepower (80 kW; 108 PS) per litre. Bizzarrini insisted the engine was mechanically capable of reaching 400 brake horsepower (298 kW; 406 PS) at 11,000 rpm with an uprated fuel system, but the design was judged adequate, and when fitted with production carburettors, all the auxiliary systems, and detuned for road use, the engine still made 280 brake horsepower (209 kW; 284 PS).