The Vauxhall C20LET OPC is a 1,998 cc, inline‑four turbocharged petrol engine produced between 1997 and 2002. It features a double overhead camshaft (DOHC), 16‑valve layout with sequential multi‑point fuel injection and a cast‑iron block with aluminium cylinder head. In standard OPC form it delivered 147 kW (200 PS) and 250 Nm of torque, providing aggressive performance with strong mid‑range response ideal for hot hatch applications.
Fitted exclusively to the Astra G Coupe OPC and limited-edition Astra G OPC models, the C20LET OPC was engineered as Vauxhall’s flagship performance engine of the late 1990s. Emissions compliance was achieved through a three‑way catalytic converter and electronic throttle control, meeting Euro 2 standards across all production years.
One documented concern is premature failure of the exhaust manifold due to thermal fatigue, highlighted in Vauxhall Engineering Bulletin EB‑98‑012. The tubular steel manifold develops cracks near the turbo flange after repeated high‑load cycles, leading to boost leaks, oxygen sensor errors, and potential turbo damage.
All production years (1997–2002) meet Euro 2 standards (VCA UK Type Approval #VCA/EMS/3210).
The Vauxhall C20LET OPC is a 1,998 cc inline‑four turbocharged petrol engine engineered for high-performance hatchbacks (1997–2002). It combines sequential multi‑point fuel injection with a Garrett T25 turbocharger to deliver responsive power delivery and track-capable acceleration. Designed to meet Euro 2 emissions standards, it prioritizes performance within regulatory limits of its era.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,998 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, DOHC, 16‑valve | |
| Aspiration | Turbocharged | |
| Bore × stroke | 86.0 mm × 86.0 mm | |
| Power output | 147 kW (200 PS) | |
| Torque | 250 Nm @ 2,400 rpm | |
| Fuel system | Bosch Motronic MPFI (sequential) | |
| Emissions standard | Euro 2 | |
| Compression ratio | 8.8:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | Garrett T25 (fixed geometry) | |
| Timing system | Belt‑driven camshafts | |
| Oil type | GM Dexos1 (SAE 10W‑40) | |
| Dry weight | 132 kg |
The turbocharged layout delivers spirited acceleration but requires GM Dexos1 (10W‑40) oil changed every 10,000 km to protect the turbo bearings and timing belt tensioner. The exhaust manifold is prone to cracking near the turbo flange—symptoms include whistling under boost and P0171/P0174 codes. Replacement with reinforced manifold per Engineering Bulletin EB‑98‑012 is recommended for track or spirited use. Use only RON 98 premium petrol to prevent knock and maintain performance calibration.
Oil Specs: Requires GM Dexos1 (10W‑40) specification (Vauxhall Workshop Manual 1999). Supersedes ACEA A3/B3 requirements.
Emissions: Euro 2 certification applies to all C20LET OPC production (1997–2002) (VCA Type Approval #VCA/EMS/3210). No Euro 3 variants exist.
Power Ratings: Measured under ISO 1585 standards. Output consistent across all OPC applications (Vauxhall TIS Doc. AST‑ENG‑020L).
Vauxhall Technical Information System (TIS): Docs AST‑ENG‑020L, ETK AST‑C20‑01
Vauxhall Engineering Bulletin EB‑98‑012
VCA Type Approval Database (VCA/EMS/3210)
ISO 1585: Road vehicles — Engine test code
The Vauxhall C20LET OPC was used exclusively in Vauxhall's Astra G performance variants with transverse mounting and no external licensing. This engine received platform-specific adaptations—upgraded engine mounts, reinforced subframe, and oil cooler in the Astra G Coupe OPC—and minor ECU calibration updates in 1999 improved boost control response, creating minor interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the front of the cylinder block near the timing cover (Vauxhall TIS AST‑ENG‑020L). The 7th VIN digit is 'C' for C20LET engines. All OPC variants use a red cam cover with "OPC" embossed. Critical differentiation from standard C20XE: C20LET has visible turbocharger, intercooler, and higher-flow fuel injectors. Exhaust manifolds are not interchangeable with non-turbo engines due to integrated turbo flange design (Vauxhall EB‑98‑012).
The C20LET OPC's primary reliability risk is exhaust manifold cracking due to high thermal loads, with elevated incidence in spirited or track-driven use. Vauxhall internal data from 2001 indicated over 16% of OPC engines required manifold replacement before 90,000 km, while UK DVSA MOT records show boost-related failures in 12% of Astra G Turbo models from this era. Aggressive driving and rapid cooldown cycles accelerate metal fatigue, making manifold inspection critical during service.
Analysis derived from Vauxhall technical bulletins (1997–2002) and UK DVSA failure statistics (2010–2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about VAUXHALL C20LET-OPC.
Comprehensive technical documentation and regulatory references
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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