Miller-Cycle Engine: Mazda’s Unique Power Solution Explained

The Mazda CX-90 represents the brand’s latest premium offering, yet this isn’t Mazda’s first venture into the luxury segment. Decades earlier, the company planned to launch its own upscale sub-brand called Amati, which would have introduced groundbreaking technology including a supercharged Miller-cycle engine. This innovative powerplant promised approximately fifty percent more power than traditional Otto-cycle engines of similar size, setting new expectations for performance and efficiency.

Although the Amati brand never reached production, Mazda repurposed its engineering investment into the 1995 Mazda Millenia sedan. This model, originally intended for Amati, debuted with a supercharged 2.3-liter Miller-cycle V6 that produced 210 horsepower and 210 pound-feet of torque. Contemporary automotive publication WardsAuto celebrated the engine as “the largest single lump of surprise and delight in the business,” recognizing its exceptional performance characteristics.

The engine’s remarkable capabilities stemmed from its unique operating principle. Ralph Miller originally developed the Miller cycle in 1957, creating a system that achieves roughly fifteen percent better efficiency than conventional internal combustion engines. This improvement comes from specialized valve timing that alters the compression stroke dynamics, allowing the engine to extract more energy from each combustion cycle while reducing pumping losses. The technology represents a sophisticated approach to balancing power output with fuel economy, demonstrating Mazda’s longstanding commitment to engineering innovation.

(Source: JALOPNIK)