SAJ Test Plant Pvt. Ltd., founded in 1969, is a testament to Indian engineering innovation, rooted in vision, self-reliance, and entrepreneurial spirit. The company was established by Mr. Prakash Jagtap, a young engineer with a distinguished academic record, who started ‘Dynamic Engineering’ in a humble garage, driven more by technical conviction than capital.
At a time when dynamometers were entirely imported, SAJ’s pioneering development of India’s first water-brake dynamometer for IC engines and induction motors marked a major industrial breakthrough. The company also introduced the country’s first vehicle chassis dynamometers for various vehicle categories.
Evolving through phases as SAJ Steel, SAJ Engineering, SAJ Froude, and now SAJ Test Plant Pvt. Ltd., the brand has always carried the legacy of S.A.J., named in honour of Sarjerao Abasaheb Jagtap, a respected teacher and author, and the father of the founder.
These innovations led to SAJ receiving the National Award for Import Substitution in 1978 from the Government of India, acknowledging its leadership in indigenous test system development.
Over the decades, SAJ has earned a reputation for excellence in the design and manufacturing of a wide range of advanced testing equipment for Engines, Vehicles, Transmissions, Electric Motors, and Turboprop Aero Engines.

• Eddy Current & Hydraulic Dynamometers (Up to 6700 kW capacity) ​
• Engine Test Beds with Accessories (Production/R&D/Durability Testing)​
• Electric Motor Test Benches (Induction, Wheel Hub, BLDC, PMSM Mid Mount) ​
• Dynamometer for Aero Engines (Gas and Steam Turbines)​
• Chassis Dynamometers for 2W / 3W / 4W (End-of-Line / R&D) (IC / EV)​
• Heavy Vehicle Chassis Dynamometers (Tractors, Forklifts, Buses) (IC / EV)​
• Garage/Workshop Testing Equipment (Dynobot Series & Brake Testers)​
• Transmission Test Rigs (Gearboxes, Axles, and e-Axles) ​
• Internationally Sourced (Agency) Test Equipments such as Swirl Test Rigs, Steering Angle Testers, and ADAS Calibration Tools​

SAJ is ISO 9001:2015 certified, and all major products carry the CE mark, ensuring compliance with global quality standards. During its joint venture with Froude Consine Ltd. (1983–1997), SAJ acquired and successfully indigenised advanced PC-compatible dynamometer technology. The Pune-based manufacturing facility is equipped to machine critical components, assemble, and verify the systems before delivery to the customer. Over the past 55 years, we have supplied more than 6,500 installations across India and built a loyal customer base comprising over 700 esteemed customers. Additionally, we have exported over 650 dynamometers globally. Business innovation and achievement motivation have been the twin engines propelling SAJ for the last five decades, a company born from the vision of a young engineer. With the success achieved and the progress made, SAJ finds both pride and purpose.​

When a vehicle moves on the road, its driven wheels, powered by the engine or motor, generate tractive force, which propels the vehicle forward by overcoming inertia, rolling resistance, and aerodynamic drag. This motion is fundamentally governed by Newton’s Second Law of Motion.
Tractive force, being a tangential force applied by the wheels to the road (or rollers), is represented as rotational torque, which can be measured using a Chassis Dynamometer.
Unlike Engine or EV Motor Dynamometers, which measure torque at the crankshaft or motor shaft, Chassis Dynamometers assess how efficiently the entire powertrain delivers torque to the wheels and, ultimately, to the road.
As a result, measuring tractive force on a Chassis Dynamometer enables engineers to assess powertrain performance under controlled, repeatable conditions. This allows for precise calibration or tuning of drivability, acceleration, and other key parameters, eliminating the need for real-world road testing.​

• Dynobot is a compact and intelligent chassis dynamometer, purpose-built for drivability testing and vehicle performance optimisation. It enables precise measurement of key parameters such as acceleration, deceleration, and tractive effort, making it a valuable tool for ensuring vehicle safety, health, and responsiveness.​
• With Dynobot, potential issues can be detected early, enabling timely diagnosis and corrective action. This proactive approach helps reduce the risk of mechanical failures and enhances overall vehicle performance.​
• A standout feature of Dynobot is its ease of use. The system’s user-friendly interface ensures even non-specialist mechanics can operate it with confidence. Its short test cycle duration prevents vehicle overheating, making it particularly well-suited for two-wheeler service centres, where space and time are often limited.​​
• Whether you’re involved in vehicle tuning, post-service validation, or performance benchmarking, Dynobot is the ideal platform. Its combination of versatility, precision, and operational simplicity makes it an essential tool for service workshops, tuning garages, performance verification centres, and OEM/EV maintenance facilities.​