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V6 PRV engine

From Alfawiki
PRV
Company typeJoint venture
IndustryAutomotive engineering
PredecessorLa Française de Mécanique (FM)
Founded1971
Defunct1998
Headquarters
Douvrin, near Lens
,
France
Area served
Automotive manufacturers
ProductsV6 engines (2.5 L to 3.0 L)
OwnerPeugeot, Renault, Volvo Cars (equal ownership)

The V6 PRV engine is an overhead camshaft V6 powerplant developed and produced by Française de Mécanique for PRV, a collaborative venture among Peugeot, Renault, and Volvo Cars. Manufactured between 1974 and 1998, this engine came in four displacement variants ranging from 2.5 L to 3.0 L, available in both SOHC and DOHC layouts with either 2- or 4-valve configurations per cylinder. Initially equipped with carburetors, it later adopted fuel injection systems to comply with emissions regulations and improve output. Turbocharged and biturbo versions were also developed, utilized by Renault, Chrysler Motors, and French supercar builder Venturi.

Following 1994, the PRV gradually gave way to a new engine jointly designed by Peugeot’s successor PSA and Renault, referred to as the ES engine by PSA and the L engine by Renault.

Corporate history

Peugeot and Renault entered into a partnership in 1966 aimed at sharing component production. This collaboration led to the creation of their first joint subsidiary, La Française de Mécanique (FM), in 1969, which operated a manufacturing plant located in Douvrin near Lens in northern France. Although the PRV engines are sometimes labeled as "Douvrin" engines, this term is more frequently associated with a series of inline-four engines produced concurrently.

In 1971, Volvo joined forces with Peugeot and Renault to establish PRV as a publicly held company with equal ownership stakes. Initially conceived as a V8 project, the consortium pivoted to developing a smaller and more fuel-efficient V6 engine in response to the 1973 oil crisis and taxation policies targeting engines larger than 2.8 liters.

The PRV engine retained the conventional V8’s 90-degree bank angle but featured crankpins spaced at 120 degrees. Renault assigned the designation Z-Type to this engine for use in the Renault 30 model, which required a V6 powerplant.

Assembly equipment was delivered to Douvrin in June 1973, with production facilities finalized by January 1974. The first PRV engines were introduced on October 3, 1974, powering the Volvo 264 (B27). By late 1975, the engine was available in at least five different vehicle models.

Volvo employed the B27 variant until 1980; from 1980 to 1986, the B28 powered Volvo vehicles including limited editions of the 240 GLT and the Volvo 760. The final Volvo iteration of the PRV, known as the B280, incorporated significant enhancements beyond the original block design and was installed in Volvo 760s (1987–1990), Volvo 780s, and some early-1990s Volvo 960s. The Volvo 262 C also utilized both B27 and later B28 versions.

Renault launched the first commercially available turbocharged PRV V6 in 1984 with the Renault 25 V6 Turbo—this marked the debut of an even-firing version featuring split crankpins alongside electronic fuel injection (EFI). Turbocharged editions appeared in vehicles such as the Renault Alpine GTA V6 Turbo, Alpine A610, and Safrane Bi-turbo (all characterized by low compression ratios). Naturally aspirated models up to 3.0 L displacement were used by Peugeot, Citroën, and Renault until production ended in 1997.

While Renault focused on forced induction for the PRV platform, Peugeot and Citroën engineered their own costly multi-valve (24-valve) versions for use in the Peugeot 605 and Citroën XM. These variants maintained compression ratios similar to Renault’s 12-valve models but featured redesigned cylinder heads aimed at simplifying maintenance. Nonetheless, they experienced camshaft wear problems due to flaws in valve actuation design; these issues were partially addressed through ceramic followers and recall campaigns.

The French supercar maker Venturi created high-performance adaptations of the PRV: their Atlantique 300 delivered from a turbocharged 12-valve 3.0 L unit; racing vehicles like the Venturi 600LM employed twin-turbocharged 24-valve engines producing over ; while road-going models such as the Venturi 400GT generated using low-compression turbocharged bottom ends combined with custom cylinder heads.

Peugeot supported endurance racing through WM Peugeot by developing a DOHC twin-cam version of the PRV for competition purposes. This car achieved a top speed record at the 24 Hours of Le Mans in 1988, reaching on the main straight before suffering engine failure.

Volvo began phasing out its involvement with PRV engines during the late 1980s; its final model powered by a PRV unit was released in 1991 before transitioning exclusively to inline engines such as its Modular inline-six introduced with the Volvo 960. Peugeot, Renault, and Citroën continued utilizing PRV engines until production ended on June 15, 1998, after approximately 970,315 units had been built.

Irregular firing sequence

The design of the original V8 engine played a key role in shaping the V6 engine configuration: its cylinder banks are positioned at 90°, instead of the more typical 60°. While V8 engines generally adopt a 90° angle for natural firing order, V6 engines achieve balanced firing intervals at 60°. The 90° V6, such as the PRV, exhibits uneven firing intervals, which were later corrected by implementing split crankshaft journals. This arrangement produces a more compact lengthwise but broader engine, enabling lower hood heights.

Early PRV engines produced between 1974 and 1985 featured uneven firing patterns. From 1984 onward, second-generation PRV engines (for example, in the Renault 25 Turbo) incorporated split crankshaft journals to ensure uniform ignition timing. Comparable configurations include the odd-fire and even-fire versions of the Buick V6 and the Maserati V6 used in the Citroën SM.

PRV engine variants

Technical specifications

Displacement 2,458 cc (150.0 cu in) 2,664 cc (162.6 cu in) 2,849 cc (173.9 cu in) 2,963 cc (180.8 cu in) 2,975 cc (181.5 cu in)
Bore × stroke 91 mm × 63 mm 88 mm × 73 mm 91 mm × 73 mm 93 mm × 72.7 mm 93 mm × 73 mm
Valve count 12 12 or 24
Engine induction Turbocharged Naturally aspirated Naturally aspirated or turbocharged
Compression ratio 8.2–8.6:1 8.8–9.5:1 8.8–10.5:1 9.5:1
7.6:1 (turbocharged) 		9.5:1
7.3–7.6:1 (turbocharged)
Power output 134–136 kW (182–185 PS; 180–182 bhp) at 5500 rpm 92–110 kW (125–150 PS; 123–148 bhp) at 5500–6000 rpm 95–143 kW (129–194 PS; 127–192 bhp) at 5500–6000 rpm 123–147 kW (167–200 PS; 165–197 bhp) at 5500–6000 rpm

184 kW (250 PS; 247 bhp) at 5000–5750 rpm (turbocharged) 		123–147 kW (167–200 PS; 165–197 bhp) at 5600–6000 rpm

184–300 kW (250–408 PS; 247–402 bhp) at 5750 rpm (turbocharged)

! Torque figures ! 276–288 N⋅m (204–212 lbf⋅ft) at 2200–4000 rpm ! 207–218 N⋅m (153–161 lbf⋅ft) at 3000–3500 rpm ! 207–255 N⋅m (153–188 lbf⋅ft) at 2750–4000 rpm ! 235–260 N⋅m (173–192 lbf⋅ft) at 3600–4600 rpm

350 N⋅m (260 lbf⋅ft) at 2900 rpm (turbocharged) ! 235–260 N⋅m (173–192 lbf⋅ft) at 3600–4600 rpm

350–456 N⋅m (258–336 lbf⋅ft) at 2900 rpm (turbocharged) |}


PRV powered automobiles

Below is a compilation of notable vehicles fitted with PRV V6 engines, categorized by engine capacity and introduction period:

  • 2975 cc:
    • Alpine A610 (1991–1993)
    • Citroën XM (1989–1993)
    • Dodge Monaco and Eagle Premier models for North American markets in the late 1980s to early 1990s
    • Venturi Atlantique variants including Venturi 300 and Venturi 400 (1994–1998)

This variety of applications demonstrates the PRV engine’s adaptability across European luxury, sports, niche vehicles, as well as selected North American automobiles, reflecting its role in diverse automotive market strategies.

PRV engines in racing

  • ALD C289 endurance prototype that competed at the 1992 24 Hours of Le Mans
  • Alpine A310 Group 4 and Group B/12 racing versions
  • Alpine A610 GT2 competition model
  • Chevron B36 endurance prototype entered in the 1987 24 Hours of Le Mans
  • Fouquet off-road buggies
  • Peugeot 504 V6 Coupé Rallye Group 4
  • Peugeot P4 V6 used in Paris Dakar rally events
  • RJ Racing Helem V6
  • Schlesser Original buggy
  • UMM Alter II off-road vehicle
  • Venturi racing cars including the Venturi 260LM, 400GTR, 500LM, and 600LM
  • WM P series prototypes that raced between 1976 and 1989 at Le Mans, notably the P80 which finished fourth in 1980, and the P88 which set a record speed of 407 km/h on the Mulsanne Straight during the 1988 race; the P88 was designed for maximum velocity rather than endurance and retired after completing only 59 laps
  • Ultima Mk1, Mk2, and Mk3 race cars

The PRV engine also formed the foundation for Alfa Romeo’s 90-degree V6 powerplant used in the 155 V6 Ti during the DTM/ITC season of 1996 starting from Silverstone. This engine utilized the PRV’s cylinder bank angle and bore spacing, which offered more room between banks compared to a standard 60-degree V6, allowing improved induction efficiency. Alfa Romeo chose this engine due to its presence in the Lancia Thema platform, which was shared with the Alfa Romeo 164, Fiat Croma, and Saab 9000.

Despite some reports suggesting that the Alfa Romeo 155 V6 Ti engine was adapted from a modified 2.6-liter V8 originally from the 1970 Alfa Romeo Montreal, homologation papers from FIA verify that a "2850 cm³" V6 production engine was homologated. The Montreal’s bore spacing did not suit the requirements for the 155 V6 Ti. The narrative involving a Montreal-derived V8 was allegedly fabricated to mislead press coverage and reassure FIAT management wary of using an engine not developed internally.

See also

External links

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