Volkswagen Group W-12 engine

Volkswagen Group have produced a number of W12 internal combustion piston engines for their Volkswagen, Audi, and Bentley marques, since 2001.[1][2]

Overview

The only mass-production W12 engine is the Volkswagen 6.0 WR12 48v, a four-bank design which was released in 2001. This engine has been used in several models from the brands Audi, Bentley, and Volkswagen, and in 2003 a turbocharged version was released.

The engine is constructed by mating two narrow-angle 15° VR6 engines at an inclined angle of 72°. The narrow angle of each set of cylinders allows just two overhead camshafts to drive each pair of banks, so the W12 engine has the same number of camshafts as a V12 engine. The W12 engine has a very compact design for a 12-cylinder engine, with the overall size of the 6.0 L engine being smaller than Volkswagen's contemporary 4.2 L V8 engine.

Variants

6.0 WR12 48v

This W12 badged W12 engine is twelve cylinder W engine of two rows of (staggered) 6 cylinders, formed by joining two imaginary 15° VR6 engine ('shortened inline-engine') cylinder blocks, placed on a single crankshaft, with each cylinder 'double-bank' now at a 72° angle.

This Volkswagen Group engine is also used with slight modification, and with the addition of two turbochargers in the Bentley Continental Flying Spur. It has also been used in a 600 hp form aboard the Volkswagen W12 prototype sports car to establish a 24-hour record of 323 km/h in 2002 at the Nardò Ring in Italy.

Identification: Parts code prefix: 07C:
Engine displacement & engine configuration: 5998 cc 72° W12 engine; bore x stroke: 84.0 x, stroke ratio: 0.93:1 – undersquare/long-stroke, 499.9 cc per cylinder, compression ratio: 10.7:1: 5952 cc 72° W12 engine; bore x stroke: 84.0 x, stroke ratio: 0.93:1 – undersquare/long-stroke, 496 cc per cylinder, compression ratio: 10.7:1:
Cylinder block & crankcase: Homogeneous monoblock low-pressure chill die cast hypereutectic 'Alusil' aluminium-silicon alloy (AlSi17Cu4Mg); torsionally stiff aluminium alloy crankcase with high-resistance cylinder liners, simplex roller chain driven oil pump; die-forged steel 21.2 kg crankshaft, seven main bearings, crankpins offset to achieve a constant firing order as on a V6 engine:
Cylinder heads & valvetrain: Cast aluminium alloy; four valves per cylinder, 48 valves total, low-friction roller finger cam followers with automatic hydraulic valve clearance compensation, double overhead camshaft driven from the flywheel side via a two-stage chain drive utilising three 3/8" simplex roller chains, continuous vane-adjustable variable valve timing for intake and exhaust camshafts with up to 52 degrees timing range for the flow-optimised inlet ports, 22 degrees on the exhaust camshafts:
Aspiration: Two air filters, two hot-film air mass meters, two throttle bodies each with electronically controlled Bosch 'E-Gas' throttle valves, four-part two-channel cast magnesium alloy intake manifold; Bentley versions also use twin-turbos – one turbocharger per VR cylinder bank:
Fuel system, ignition system, engine management: Two linked common rail fuel distributor rails, multi-point electronic sequential indirect fuel injection with twelve intake manifold-sited fuel injectors; centrally positioned NGK longlife spark plugs, mapped direct ignition with 12 individual direct-acting single spark coils; Bosch Motronic ME 7.1.1 electronic engine control unit (ECU), cylinder-selective knock control via four knock sensors, permanent lambda control, water-cooled alternator:
Exhaust system: Two vacuum-controlled secondary air injection pumps for direct injection into exhaust ports to assist cold start operation, four exhaust manifolds with four integrated ceramic catalytic converters, eight heated oxygen sensors monitoring pre- and post catalyst exhaust gases:
Dimensions: Length: 513 mm: Height: 715 mm: Width: 710 mm, then 690 mm
DIN-rated motive power & torque outputs – Audi / Volkswagen, ID codes
309 kW; 550 Nm — Audi A8: AZC (01/01-09/02), VW Phaeton: BAN (04/02-05/05)
331 kW at 6,200 rpm, 580 Nm at 4,000 rpm, 560 Nm at 2,300–5,300 rpm — Audi A8: BHT, BSB, BTE (12/03-07/10)
331 kW at 6,000 rpm; 560 Nm at 2,750–5,000 rpm — Phaeton: BRN, BTT (05/05-03/16)
331 kW at 6,000 rpm; 600 Nm at 3,300 rpm — Touareg: BJN, CFRA (08/04-05/10)
DIN-rated motive power & torque outputs – Bentley twin turbo
412 kW at 6,100 rpm; 650 Nm at 1,600–6,100 rpm — standard models: BWR, BEB, MTBHT
449 kW at 6,000 rpm; 750 Nm at 1,700–5,600 rpm — "Speed" models: CKHC, BWRA
522 kW at 5,900 rpm; 1017 Nm at 2,050–4,500 rpm — "Supersports" model
Applications (5998cc): Audi A8 (AZC: 03/01-09/02, BHT: 02/04-, BSB: 10/04-, BTE: 02/05-), Volkswagen Phaeton (BAN: 05/02-05/05, BRN: 05/05-10/08, BTT: 05/05-10/08) , Volkswagen Touareg sport (BJN: 08/04-, CFRA: 02/08-) , Bentley Continental GT, Bentley Continental Flying Spur:

Applications (5952cc)

Bentley Continental GT, Bentley Continental Flying Spur, Bentley Bentayga

6.0 WR12 48v TFSI

This engine produces 430 kW of power and 800 Nm of torque. It would mostly share the same technical specifications with its turbocharged 6.0-liter predecessor, other than the fact that it was modified to meet new WLTP emission standards. This new engine was promised to be made available on the fourth generation A8, following S8 and 60 TFSI/TDI models. However, as of August 2020, only examples of the W12 variant were press cars. It is rumoured that the W12 variant is only available as special orders in selected European dealerships.

Applications (5952cc)

Bentley Continental GT, Bentley Continental Flying Spur, Bentley Bentayga

6.0 WR12 48v TFSI

6.3 WR12 48v FSI (CEJA)

This engine produces 500 PS of power and 625 Nm of torque. This new engine was made available on the 3rd generation A8. It had more compact dimensions than a comparable V8 engine FSI direct injection with twin high-pressure fuel pumps, twin fuel rails, and six-port high-pressure injectors.

Applications
A8 L W12 6.3 FSI quattro (CEJA)

manufacturer	Volkswagen Group
production	2001-April 2024
configuration	72° W-12
bore	84 mm
stroke	90.2 mm, 89.5 mm
displacement	5998 cc, 5952 cc
valvetrain	48-valve, DOHC, four-valves per cylinder
turbocharger	Twin-turbocharged
power	414-700 hp
torque	405-750 lbft
fuelsystem	Fuel injection
compression	10.7:1
fueltype	Gasoline
oilsystem	Dry sump
weight	239 kg

Overview

Variants

6.0 WR12 48v

Applications (5952cc)

6.0 WR12 48v TFSI

Applications (5952cc)

6.0 WR12 48v TFSI

6.3 WR12 48v FSI (CEJA)

Applications

References