Which of the following engines would be acceptable for Piper model PA22-150, serial number 22-3389?

The correct choice is the Lycoming O-320-A2A engine, which is an appropriate powerplant for the Piper model PA22-150, serial number 22-3389. This engine is compatible in terms of power output, weight, and design specifications that align with what the PA22-150 was intended to operate. The O-320 series, including the A2A variant, is known for its reliability and has been widely used in various civilian aircraft, including Pipers, due to its performance characteristics.

In general, when selecting an engine for a specific aircraft model, factors such as proper horsepower rating, installation compatibility, and adherence to aircraft type certificate specifications are essential. The O-320 engine family fits the PA22-150 design requirements, ensuring optimal performance and safety.

The other engines listed, while they may have some similarities, do not meet the specific requirements for this aircraft model due to variations in horsepower, installation configurations, or manufacturer specifications that differ from the approved types for this particular Piper aircraft. Thus, selecting the O-320-A2A is not only correct but essential for maintaining airworthiness and compliance with regulatory standards.