H22: How Do I Know If It's Been Decked?

Which H22 is closed deck?

The Honda H22A engine is the closed-deck variant within the H22 series. A closed-deck design refers to the engine’s cylinder bores being fully enclosed by the cylinder head and block, creating a stronger, more rigid structure compared to open-deck configurations. This design enhances durability, especially under high-performance conditions, and improves cylinder sealing. The H22A is commonly found in vehicles like the Acura TL (Type SH2) and later Honda Accord Si, where its reinforced architecture supports higher compression ratios and forced induction modifications.

Key Features of the H22A Closed-Deck Engine:

- Structural Integrity: The closed-deck design reduces bore distortion under stress, making it ideal for high-horsepower applications.
- Cooling Efficiency: The block’s reinforced walls improve heat dissipation, preventing detonation during aggressive driving.
- Compatibility: It is favored in aftermarket tuning due to its robust construction, often paired with turbochargers or superchargers.

Other H22 variants, such as the H22A1 or earlier models, may use a semi-open or open-deck configuration, which lacks the full block-to-head enclosure. The closed-deck H22A distinguishes itself by its rectangular main bearing caps and thicker deck surfaces, traits that set it apart for performance-oriented builds. Identifying a closed-deck H22 requires checking the block casting number (e.g., “H22A” stamped on the front) and visually inspecting the cylinder walls for full enclosure.

What size engine is a H22?

The H22 is a 3.0-liter V6 engine developed by Honda, known for its balance of power and efficiency. Officially displacing 2,995 cubic centimeters (cc), it is categorized as a 3.0L engine. This engine is part of Honda’s H-series lineup and is commonly found in vehicles like the Acura TL, Honda Odyssey, and certain Acura MDX models from the late 1990s to the mid-2000s. Its V6 configuration features six cylinders arranged in a 60° V-angle, optimized for compact packaging and smooth operation.

Key Specifications of the H22 Engine

The H22’s displacement is determined by its bore (94 mm) and stroke (84 mm) dimensions. Each cylinder’s bore (diameter) and stroke (piston travel) contribute to the total displacement using the formula:
- Bore: 94 mm
- Stroke: 84 mm
- Total cylinders: 6
This results in a precise 2,995 cc displacement when calculated using engine displacement formulas, rounding to the widely recognized 3.0-liter specification.

Applications and Variants

While the base displacement remains consistent, the H22 has seen minor variations across different models and years. For example:
- H22A1: Found in early Acura TL models (1997–2000)
- H22A2: Used in later Acura TL (2001–2004) and Honda Odyssey (2001–2003)
- H22A3: Featured in the 2005–2009 Acura TL and some Acura MDX trims
These variants often included tuning adjustments for horsepower and torque but retained the core 3.0L displacement. The engine’s size made it suitable for midsize luxury sedans and SUVs, emphasizing both performance and fuel efficiency.