In practice, the W8 engine is created from two narrow-angle (15 degree) VR4 engines mounted at an angle of 72 degrees from each other on a common crankshaft. Thus, the resulting four banks align to form a "W".
W8 engines are much less common than V8 engines, and the only W8 engine to reach production was manufactured by Volkswagen from 2001–2004.
This engine had a displacement of 3,999 cc (4 L), had a peak power rating of 202 kW (271 hp) at 6,000 rpm and a peak torque rating of 370 N⋅m (273 lb⋅ft) at 2,750 rpm. Power and torque outputs were lower than competitors V8 engines with similar capacity, however the W8 engine was praised for its smoothness.
Sales of the W8-engined Passat models were poor, and production was discontinued when the next generation of Passat switched from a longitudinal engine to a transverse engine layout, which made packaging of the wide W8 engine difficult. The W8 was effectively replaced by the Volkswagen 3.6-litre VR6 petrol engine.
4.0 WR8 32v 202kW
The 'W8' badged engine is an eight-cylinder W engine of four banks of two cylinders, formed by joining two 15° VR4 engines, placed on a single crankshaft, with each cylinder 'double-bank' now at a 72° vee-angle.
parts code prefix: 07D, ID codes: BDN (09/01-09/04), BDP (05/02-09/04)
engine displacement & engine configuration
3,999 cc (244.0 cu in) 72° WR8 engine; bore x stroke: 84.0 mm × 90.2 mm (3.31 in × 3.55 in), stroke ratio: 0.93:1 – undersquare/long-stroke, 499.9 cc per cylinder, compression ratio: 10.8:1
cylinder block & crankcase
cast aluminium alloy with two-part cast aluminium alloy oil sump; five main bearings; die-forged steel crankshaft with split crankpins; Lanchester principle balance shafts one above the other, counter-rotating at twice the crankshaft speed, symmetric to the middle of the crankshaft, upper one driven by a toothed belt
cylinder heads & valvetrain
cast aluminium alloy; four unequal-length valves per cylinder, 32 valves total, low-friction roller finger cam followers with automatic hydraulicvalve clearance compensation, simplex roller chain-driven (relay method, using three chains) double overhead camshafts, continuous vane-adjustable variable valve timing for intake and exhaust camshafts with up to 52° variance inlet camshafts and 22° for exhaust camshafts
two linked common rail fuel distributor rails, multi-point electronic sequential indirect fuel injection with eight intake manifold-sited fuel injectors; centrally positioned NGK longlife spark plugs, mapped direct ignition with eight individual direct-acting single spark coils; Bosch Motronic ME electronic engine control unit (ECU), cylinder-selective knock control via four knock sensors, permanent lambda control; 95 RON/ROZ(91 AKI) EuroSuperPlus (premium) unleaded recommended for maximum performance and fuel economy
vacuum-operated secondary air injection pump for direct injection into exhaust ports to assist cold start operation, one cast iron exhaust manifold per cylinder bank with integrated ceramic catalytic converter per cylinder bank, four heated oxygen sensors monitoring pre- and post catalyst exhaust gasses, EU4 compliant
mass: 190 kg (419 lb), length: 420 mm (16.5 in) length, width: 710 mm (28.0 in), height: 683 mm (26.9 in)
DIN-rated motive power & torque output
202 kW (275 PS; 271 bhp) at 6,000 rpm; 370 N⋅m (273 lbf⋅ft) at 2,750 rpm (11.6 bar (168 psi) MEP); max. engine speed: 6,400 rpm (19.2 m/s)