Here’s a revised version with reduced passive voice, more transitions, and improved segmentation:

The product range includes Cummins engines from the B, C, D, L, and Z series platforms. These engines are designed to comply with National V and National VI emission standards for vehicles, as well as Non-Road National IV standards.

Engine Specifications
These engines offer a variety of displacements, including 3.9L, 4.5L, 5.9L, 6.7L, 8.3L, 8.9L, 9.5L, and 13L, providing a wide power range from 60 to 770 horsepower. This flexibility ensures that they meet the needs of various applications, from light to heavy-duty operations.

Versatile Applications
As a result, these engines are widely used in a broad range of industries, including:
Light, medium, and heavy-duty trucks, delivering reliable performance for transportation and logistics.
Mid-to-high-end intercity coaches, providing efficient and comfortable long-distance travel.
Large and medium-sized public buses, offering durability and fuel efficiency for public transportation.
Construction machinery, powering equipment in demanding environments such as construction and infrastructure projects.
Marine main and auxiliary engines, delivering essential power for vessels across different sectors.
Power generation sets, providing dependable energy solutions for industrial and residential use.

By offering such a diverse range of engines, Cummins ensures high performance, fuel efficiency, and reliability across various industries.

This version uses active phrasing and includes transitions like “As a result,” “This flexibility ensures,” and “By offering” to guide the reader and improve readability.