Mazda ND Performance Enhancements for Street and Autocross

There’s something inherently special about the Mazda Miata. Light, nimble, and endlessly fun to drive, the ND-generation Miata is a brilliantly engineered sports car straight from the factory. But for those who want to extract even more performance, especially in the context of autocross competition, the stock setup is just the beginning. In this comprehensive, data-driven guide, Robert Wagoner takes readers through the full journey of tuning his 2021 Miata ND. Starting with suspension upgrades tailored for the SCCA Solo AST class, and moving through detailed fuel testing, weight reduction strategies, and ECM tuning, this book lays out a clear, practical roadmap for unlocking the Miata’s full potential.With over two decades of hands-on autocross experience and a background in electrical engineering, the author brings both technical rigor and enthusiast passion to the table. This is not just a collection of theories or generic mod advice; it’s a real-world performance chronicle grounded in measurable results. Wagoner walks readers through alignment specs, coilover choices, sway bars, tire setups, weight reductions, and other suspension upgrades. He compares his own setup with two other competitive Miata ND builds, optimized differently within AST class rules, and each proven on the autocross course with Fastest Time of Day (FTD) results. Under the hood, the book goes even deeper. With no hardware changes to the engine, Wagoner explores the surprisingly strong capabilities of the stock Miata ND ECM across different fuel types, with a particular focus on ethanol content. He details dyno results from testing various octane fuels, E85 blends, and the effects of tuning ignition timing, fuel injection, and cam timing to extract more power safely and reliably. Readers will learn how to achieve meaningful horsepower gains, over 10 HP, simply through fuel and ECM optimization. The book also covers important lessons learned, including what not to waste time on, based on extensive testing. Whether you’re a novice looking to get started or a seasoned racer chasing tenths of a second, this book delivers a rare mix of technical depth, practical advice, and personal experience that makes it an essential read for any serious Miata enthusiast.