The Mack E9 V8 engine stands as a legend in the trucking industry, renowned for its immense power, distinctive “thumping throb” exhaust note, and unique position as the only truly successful four-stroke diesel V8 designed for heavy-duty trucks. This engine, capable of producing up to 500 hp in its original form, has left an indelible mark on trucking history.
A Mack E9 V8 engine demonstrating its power while pulling a grade.
The Genesis of the Mack Diesel V8
Mack Trucks, an early adopter of diesel technology, began experimenting with diesel engines in the 1920s. After extensive research and development, including collaborations with European manufacturers like Mercedes-Benz, Mack introduced its first production diesel, the ED 519, in 1938. This engine utilized the Lanova “Energy Cell” combustion chamber for efficient combustion and lower injection pressures.
A 1950 Mack LJT, showcasing the company’s early adoption of diesel technology.
A pivotal partnership with Scania-Vabis in 1950 led to the adoption of Scania’s direct injection technology, resulting in the legendary END 673 “Thermodyne” diesel engine. This collaboration laid the groundwork for the future development of the Mack V8.
A 1962 Mack advertisement highlighting the innovative Thermodyne diesel engine.
The Birth of the Mack V8: The END 864
In 1962, Mack unveiled the END 864, a groundbreaking 90-degree V8 displacing 864 cubic inches. This engine, producing 255 hp and 638 lb-ft of torque, offered significant advantages in terms of displacement and packaging compared to inline-6 designs.
A 1964 Mack truck equipped with the revolutionary END 864 V8 engine.
While powerful, the END 864 faced challenges with its Bosch PSJ injection pump’s sensitivity to fuel contamination and a tendency for head gasket failures. These issues would be addressed in subsequent iterations of the Mack V8.
Evolution and Refinement: The 865 and 866
The Mack V8 underwent a significant redesign in 1969, resulting in the 865 (Maxidyne) and 866 models. These engines featured increased displacement, strengthened internal components, and a transition to a single turbocharger and a more reliable Bosch in-line injection pump. The Maxidyne version, designed for low-end torque and fuel efficiency, was particularly innovative.
The Mack ENDT 865 Maxidyne V8 engine, known for its low-end torque and fuel efficiency.
The Rise of the E9
By the late 1970s, the need for even greater power led to the development of the E1000, later renamed the E9. This engine boasted a displacement of 998 cubic inches and power outputs ranging from 360 to 400 hp, laying the foundation for even more powerful versions in the future.
The Mack E9 V8 engine, a powerhouse in the trucking industry.
The Legacy of the Mack E9 V8
The Mack E9 V8 engine, with its impressive power and distinctive sound, cemented its place as a true icon in the trucking world. Although discontinued in 2003, its influence can still be felt in the industry, and its legacy continues to inspire enthusiasts and truckers alike. The E9’s robust design, powerful performance, and unique character ensured its enduring popularity and cemented its status as a legend in trucking history.
