The Honda C27A1 is a 2,656 cc, 90 — degree V6 naturally aspirated petrol engine produced between 1988 and 1990. It features a single overhead camshaft per bank (SOHC) with 24 valves and Honda's PGM‑FI fuel injection system. This configuration prioritized smooth, refined power delivery and strong low — to — mid — range torque for executive sedans.
Fitted primarily to the first — generation Honda Legend (KA chassis), the C27A1 was engineered for quiet, effortless cruising an…

Honda
Production years 1988–1990 meet applicable late-1980s emissions standards for respective markets (e.g., US EPA Tier 0, California ARB, Japanese Showa 58).
The Honda C27A1 is a 2,656 cc 90-degree V6 naturally aspirated petrol engine engineered for executive sedans (1988-1990). It combines PGM‑FI electronic fuel injection with a 24‑valve SOHC layout to deliver exceptionally smooth, linear power and strong low-end torque. Designed to meet late-1980s emissions standards, it balances refinement with mechanical sophistication.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,656 cc | |
Fuel type | Petrol | |
Configuration | 90° V6, SOHC, 24-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 81.0 mm × 86.0 mm | |
Power output | 127 kW (172 PS) @ 5,800 rpm | |
Torque | 234 Nm @ 4,500 rpm | |
Fuel system | Honda PGM‑FI (Programmed Fuel Injection) | |
Emissions standard | US EPA Tier 0 / California ARB / Japanese Showa 58 | |
Compression ratio | 9.6:1 | |
Cooling system | Water‑cooled | |
Turbocharger | None | |
Timing system | Chain‑driven | |
Oil type | API SF/SG 10W‑40 | |
Dry weight | 168 kg |
The Honda C27A1 was used exclusively in Honda's flagship KA platform with longitudinal mounting. This engine received no significant platform-specific adaptations or facelift revisions during its short production run, ensuring broad parts interchangeability. All specifications are documented in OEM technical bulletins.
The C27A1's primary reliability risk is balance shaft bearing wear, with elevated incidence in high-mileage or poorly maintained examples. Honda service data indicates vibration complaints are a common cause for diagnostic visits, while valve train noise often stems from neglected clearance adjustments. Adherence to the 30,000 km service interval makes long-term reliability excellent.
Analysis derived from Honda technical bulletins (1988-1990) and US NHTSA complaint data (1988-1995). Repair procedures should follow manufacturer guidelines.
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Yes, the C27A1 is generally very reliable long-term when properly maintained. Its robust V6 design and non-interference nature make it durable. The keys to longevity are regular oil changes, timely valve adjustments, and addressing balance shaft issues promptly if vibration is detected.
The most frequent issues are worn balance shaft bearings causing vibration, valve train noise from neglected adjustments, and fuel system faults (injectors, pressure regulator) in the PGM-FI system. Cooling system leaks from aging hoses and gaskets are also common on high-mileage examples.
The C27A1 was used exclusively in the first-generation Honda Legend (KA chassis) from 1988 to 1990. It was fitted to all trim levels (Base, L, LS) in North America and Japan during this period.
Modest power gains are possible. Common upgrades include a performance exhaust and cold air intake. Significant power increases are difficult without internal modifications or an engine swap to the larger C32A, as the engine management system is relatively basic and not easily remapped.
Fuel economy is typical for a smooth V6 of its era. Expect around 17-19 mpg (US) in city driving and 23-26 mpg (US) on the highway for a Legend sedan with an automatic transmission. Real-world figures vary with condition and driving style.
No. The Honda C27A1 is a non-interference engine. If the timing chain were to fail, the pistons and valves will not collide, preventing catastrophic internal engine damage. This is a significant design advantage for long-term ownership.
Honda originally specified API SF/SG 10W-40 motor oil. Modern high-quality 10W-40 or 5W-30 oils meeting API SL, SM, or higher specifications are perfectly suitable and often recommended for their superior protection and flow characteristics.
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