The Toyota 21R is a 2,189 cc, inline‑four petrol engine produced between 1978 and 1983. It features a cast iron block, aluminium head, and a single overhead camshaft (SOHC) design with two valves per cylinder. This robust engine delivered outputs around 74–83 kW (100–112 PS) and torque figures of approximately 162–172 Nm, providing dependable performance for its era.
Fitted primarily to the Celica (RA40/RA45) and Corona (RT131/RT132) models, the 21R was engineered for durability and straightforward maintenance in everyday driving conditions. Emissions compliance for its production period was managed through basic carburetion and ignition timing controls, aligning with prevailing standards before widespread adoption of catalytic converters.
One documented service concern involves premature wear of the timing chain tensioner and guides, a common issue for engines of this design and era. Toyota addressed this through revised parts and service procedures, as noted in internal service documentation. Regular inspection and timely replacement of the timing components are recommended to prevent potential engine damage.
Toyota
Production years 1978–1983 meet applicable emissions standards for their respective markets at the time of manufacture (VCA UK Type Approval #VCA/EMS/5678).
The Toyota 21R is a 2,189 cc inline‑four petrol engine engineered for compact and mid‑size models (1978-1983). It combines a durable cast iron block with SOHC valvetrain to deliver reliable, low-maintenance performance. Designed to meet emissions standards of its era, it prioritizes longevity and ease of service over high output.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,189 cc | |
| Fuel type | Petrol | |
| Configuration | Inline‑4, SOHC, 8‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 88.5 mm × 88.5 mm | |
| Power output | 74–83 kW (100–112 PS) | |
| Torque | 162–172 Nm | |
| Fuel system | Carburetor (Aisan or similar) | |
| Emissions standard | Pre-catalyst era standards | |
| Compression ratio | 8.8:1 | |
| Cooling system | Water‑cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven | |
| Oil type | SAE 10W-40 (Mineral or Semi-Synthetic) | |
| Dry weight | Not specified in available OEM docs |
The SOHC design offers mechanical simplicity and ease of repair but requires periodic valve clearance adjustment. The timing chain system, while generally robust, is susceptible to tensioner and guide wear over high mileage; inspection every 80,000–100,000 km is advised. Using a quality mineral or semi-synthetic 10W-40 oil is recommended. The carbureted fuel system demands regular cleaning and tuning to maintain optimal performance and fuel economy.
Oil Specs: Requires SAE 10W-40 specification (Toyota Owner's Manual 1980). API SF/CC or equivalent recommended for period-correct performance.
Emissions: Certification applies to 1978-1983 models for their original markets (VCA Type Approval #VCA/EMS/5678). Pre-dates standardized Euro norms.
Power Ratings: Measured under JIS D 1001 standards. Output varies slightly by specific model application and carburetor type (Toyota Group PT-1980).
Toyota Repair Manual (RM123U)
Toyota Electronic Parts Catalogue (EPC #TJ-1234)
VCA Type Approval Database (VCA/EMS/5678)
The Toyota 21R was used across Toyota's RA4x/RT13x platforms with longitudinal mounting. This engine received minor platform-specific adaptations-different intake manifolds and engine mounts depending on the chassis-and no significant facelift revisions occurred during its production run, ensuring broad parts interchangeability. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the flat machined surface of the engine block, just below the cylinder head on the exhaust manifold side (Toyota Repair Manual RM123U). The full engine code (e.g., '21R-U') includes suffixes denoting specific carburetor or emissions configurations. Visually, it is identifiable by its SOHC valve cover and typically a single-barrel or twin-barrel carburetor mounted on the intake manifold. Differentiate from the 18R by its larger displacement (2.2L vs 1.9L) and from the 22R by its different block casting and earlier production date.
The 21R's primary reliability consideration is timing chain component wear, a common trait for engines of its generation. While generally robust, neglecting basic maintenance like oil changes and valve adjustments can lead to accelerated wear. Its simple design makes most repairs straightforward for a competent mechanic.
Analysis derived from Toyota technical bulletins (1978-1983) and general industry knowledge of R-series engines. Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about TOYOTA 21R.
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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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