VR5 engine

Summary

The VR5 engines are a family of petroleum fuelled Internal combustion engines developed by the Volkswagen Group and produced from 1997 to 2006[citation needed]. They are derived from the VR6 engine family,[1] also developed by Volkswagen, but with one less cylinder. VR5 engines are narrow-angle V5 petrol engines, with a V angle of 15° and a displacement of 2,324 cc (2.3 L; 141.8 cu in). The VR5 was the first production block to use five cylinders in a V design with a 15-degree angle.

VR5
Overview
ManufacturerVolkswagen
Also calledV5
Production1997 (1997) to 2006 (2007)
Layout
ConfigurationV5
Displacement2,324 cc
Cylinder bore81.0mm
Piston stroke90.2mm
Block materialGrey cast iron
Head materialCast aluminium alloy
Valvetrain10 valve (AGZ) or 20 valve with variable valve timing (AQN/AZX), one direct acting cam per cylinder bank
Compression ratio10:1 (AGZ) or 10.8:1 (AQN/AZX)
RPM range
Redline6500 RPM
Combustion
Fuel systemCommon rail multi-point electronic sequential indirect fuel injection with five intake manifold-sited fuel injectors
ManagementBosch Motronic M3.8.3 (AGZ)
Fuel typePetrol
Oil systemWet sump
Output
Power output150 PS (AGZ) to 170 PS (AQN/AZX)
Torque output209 N⋅m (AGZ) to 220 N⋅m (AQN/AZX)
Emissions
Emissions control technologyThree-way catalytic converter with lambda control and exhaust secondary air injection
Chronology
PredecessorNone
SuccessorNone

Technical InformationEdit

A VR5 engine block consists of two cylinder banks, one bank containing three cylinders and the other containing two. In a transverse layout the three cylinder bank is located towards the front and in a longitudinal layout towards the right. Due to the narrow angle the cylinder arrangement appears like a staggered inline five cylinder. The engines have a firing order of 1-2-4-5-3.

The VR5 was initially made with 2 valves per cylinder as the AGZ engine from 1997 until 2000, resulting in a 10 valve engine producing 150 PS (110 kW; 148 hp) at 6000 RPM and 209 N⋅m (154 lb⋅ft) of torque at 3200 RPM. The engine was updated in 2000 as the AQN/AZX engine adding an additional 2 valves per cylinder and variable valve timing, resulting in an 20 valve engine now with 4 valves per cylinder, producing 170 PS (125 kW; 168 hp) at 6200 RPM and 220 N⋅m (162 lb⋅ft) at 3300 RPM. Both versions of the engine had cast aluminium alloy cylinder heads and cast iron cylinder blocks.[2][1]

AGZ engineEdit

Valvetrain and cylinder headEdit

The AGZ engine was the first version of the VR5. It had ten valves in total, with two unequal sized valves per cylinder and chain driven camshafts. Due to the use of a single cylinder head, a key design principle of the VR engines, exhaust and intake ports were of unequal length between the two cylinder banks. To mitigate this, Volkswagen used unequally sized valves to ensure even flow and power output from the cylinders.[citation needed]

Engine block and pistonsEdit

The AGZ engine used a cast iron cylinder block with five staggered cylinders. Each cylinder was 81.0 mm × 90.2 mm (3.19 in × 3.55 in) bore x stroke, resulting in 464.8 cc (28.4 cu in) per cylinder with a 0.90:1 stroke ratio (undersquare/long stroke). The top of each piston was angled to accommodate for the use of the 15° narrow V angle.

Aspiration, fuel system, and engine managementEdit

The AGZ engine was managed by a Bosch Motronic M3.8.3 engine management system. The engine used multi-point common rail sequential fuel injection, with fuel injected indirectly into the lower intake manifold section just before the cylinder head intake ports. Fuel and air delivery was controlled by a cable operated throttle body, with a potentiometer monitoring throttle position and allowing the Motronic ECU to deliver the correct amount of fuel. The engine also had a vacuum actuated variable intake manifold, controlled by the ECU via a valve part of the engines vacuum system. The valve is opened and closed depending on engine load, engine speed and throttle position. This allows the engine to take advantage of pressure waves created by the intake valves opening and closing.

VR5 Engine Versions
Engine Code Production Displacement Power(PS) Torque Compression ratio
AGZ 1997–2000 2324 cc 150 @ 6000 RPM 209 N⋅m (154 lb⋅ft) @ 3200 RPM 10:1
AQN/AZX 2000–2006 2324 cc 170 @ 6200 RPM 220 N⋅m (162 lb⋅ft) @ 3300 RPM 10.8:1

The VR5 was used in the Volkswagen Golf, Bora, New Beetle and Passat. The engine was also included in the Toledo, a saloon car made by Volkswagen Group's subsidiary SEAT.[2]

ReferencesEdit

  1. ^ a b "Self-Study Programme 195 The 2.3 ltr V5 Engine – Volkspage" (PDF). Volkspage. 1 May 2019. Archived from the original (PDF) on 8 May 2018.
  2. ^ a b "List of discontinued Volkswagen Group petrol engines", Wikipedia, 30 April 2019, retrieved 1 May 2019