Mercedes-AMG is discontinuing the four-cylinder C63 after misreading customer appetite for smaller engines in its flagship performance sedan. The decision comes despite the hybrid powertrain's superior power output compared to the previous V8, highlighting that performance figures alone don't satisfy enthusiast expectations. The company had hoped the electrified 2.0-liter would meet Euro 7 emissions standards while delivering thrilling performance.

Outgoing CEO Michael Schiebe acknowledged that projections were overly optimistic about customer acceptance of the downsized engine. In interviews with German automotive publications, he admitted the company overestimated market willingness to embrace the four-cylinder configuration, particularly in key markets like the United States. This marks the second time Schiebe has candidly addressed the C63's challenges, previously acknowledging that some customers simply prefer V8 engines regardless of technological advances.

The C63's demise doesn't signal the end for the "M139" engine family, which will continue in the A45 hot hatch and likely the GLC 63 replacement. Stefan Weckbach, former Porsche Taycan chief, takes over as AMG's new CEO in July, inheriting both the challenge of satisfying enthusiast demands and meeting increasingly stringent emissions regulations. While a V8-powered C-Class isn't planned, Mercedes is developing a new eight-cylinder engine for larger models, suggesting the company is recalibrating its performance strategy based on real-world customer feedback.

Quick Fact: The C63's four-cylinder engine was officially designated the "M139" in Mercedes-AMG's nomenclature.