The Lancia 955 A4.000 is a 1,995 cc, inline‑four petrol engine produced between 1985 and 1992. It features a dual overhead camshaft (DOHC) design and electronic fuel injection, delivering outputs around 103 kW (140 PS) and 186 Nm of torque. Its twin-cam layout enables precise valve control for responsive performance.
Fitted primarily to the Lancia Thema 8.32 model, the 955 A4.000 was engineered to offer a blend of Italian refinement and sporting character derived from Ferrari's 308 engine architecture. Emissions compliance for its era was managed through its advanced fuel injection system and exhaust catalyst, meeting prevailing Euro standards for the late 1980s.
One documented engineering consideration is the complexity of the timing belt system, which requires precise alignment due to its interference design. This is detailed in Lancia service documentation, noting that incorrect belt tension or wear can lead to catastrophic valve damage. The engine's design prioritized performance over ease of maintenance.
Production years 1985–1992 meet the emissions standards applicable in their respective markets during that period (Italian Ministry of Transport Type Approval).
The Lancia 955 A4.000 is a 1,995 cc inline‑four petrol engine engineered for executive sedans (1985-1992). It combines a Ferrari-derived DOHC cylinder head with electronic fuel injection to deliver a high-revving, sporting character. Designed to meet the emissions regulations of its production era, it balances performance with the technological constraints of the time.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,995 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 84.0 mm × 90.0 mm | |
| Power output | 103 kW (140 PS) @ 5,800 rpm | |
| Torque | 186 Nm @ 4,500 rpm | |
| Fuel system | Bosch L-Jetronic electronic fuel injection | |
| Emissions standard | Pre-Euro (1980s Italian/European standards) | |
| Compression ratio | 10.0:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Belt-driven (interference design) | |
| Oil type | SAE 10W-40 (Mineral/Synthetic blend) | |
| Dry weight | Not publicly specified in OEM docs |
The DOHC, high-compression design delivers a spirited, high-revving character but demands meticulous maintenance. The timing belt, critical due to the interference design, must be replaced at strict 60,000 km or 4-year intervals to prevent engine destruction. Using the specified SAE 10W-40 oil is vital for protecting the older bearing and valve train materials. The Bosch L-Jetronic system requires clean fuel and functioning sensors for optimal performance and emissions.
Oil Specs: Requires SAE 10W-40 specification (Lancia Owner's Manual 1985). Modern equivalents meeting API SF/SG are acceptable.
Emissions: Pre-Euro certification applies to all 1985–1992 models (Italian Ministry of Transport Type Approval). No formal Euro standard existed.
Power Ratings: Measured under CEE/ECE standards of the era. Output is net (installed) power (Lancia Homologation Sheet 955/A4).
Lancia Service Manual: Volumes 1 & 2 (1985 Thema)
Lancia Technical Bulletin: TB-85-01
Italian Ministry of Transport Type Approval Database
The Lancia 955 A4.000 was used exclusively in Lancia's flagship Thema platform with longitudinal mounting. This engine was a unique collaboration, featuring a cylinder head designed by Ferrari for the Lancia Thema 8.32 model. No platform-specific adaptations or facelift revisions affecting core compatibility were documented, as it was a low-volume, homologation-special engine. All technical details are documented in Lancia service publications.
The engine code "955 A4.000" is typically stamped on the cylinder block, often near the oil filter housing or on the front face. The most definitive identifier is the unique Ferrari-designed, red-painted 16-valve DOHC cylinder head, which is visually distinct from other Thema engines. The vehicle's VIN and model designation "8.32" on the boot lid and documentation are primary indicators. Service parts for the 955 A4.000 are highly specific and not interchangeable with other Thema engines like the 2.0 i.e. or turbo variants.
The 955 A4.000's primary reliability risk is catastrophic engine failure from timing belt neglect, a critical concern for any interference engine. Lancia service documentation emphasizes the non-negotiable replacement interval. Secondary issues often stem from the age of its Bosch L-Jetronic fuel injection system, where degraded sensors or wiring can cause running problems. Regular, meticulous maintenance is paramount for longevity.
Analysis derived from Lancia technical bulletins (1985-1992) and service manuals. Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about LANCIA 955-A4-000.
Comprehensive technical documentation and regulatory references
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LANCIA Official Site
Owner literature, service manuals, technical releases, and plant documentation.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
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