This weekend, the NASCAR Cup Series and NASCAR Xfinity Series will make their inaugural appearance at the Autódromo Hermanos Rodríguez in Mexico City. With the circuit situated at an elevation exceeding 7,000 feet, race engineers face a unique set of challenges due to the thinner air pressure that affects vehicle performance. Key areas impacted include engine power, tire wear, fuel consumption, and overheating.
Scott Maxim, the powertrain director at Hendrick Motorsports, is leading his team to develop competitive engines that can withstand these conditions. Given that there are no other tracks on the schedule similar to Mexico City’s high altitude, the engineering team is working under significant time constraints, having to complete all cars before last weekend’s race at Michigan International Speedway.
Maxim notes the lack of reference points from other tracks at similar elevations, with the closest being Sonoma, California, which is at sea level. The team is leveraging general road course knowledge and data from other racing series to optimize engine design for the unique conditions of Mexico City. “While we maintain our build specifications, our primary focus is on the engine’s operating RPM range, which can vary from 3,500 to 9,000 RPM,” Maxim explained. This allows for an optimization in relation to power output at critical moments such as corner exits.
The challenges presented by high altitude include not only power loss due to decreased air density—estimated at around 22%—but also implications for fuel consumption. Maxim indicated that a naturally aspirated engine like those used in NASCAR will experience a corresponding drop in power and require careful tuning to adapt to the denser air.
Moreover, these changes necessitate adjustments to the car’s cooling systems, which rely on airflow for cooling engine components, including water and oil cooling systems. Maxim concluded that their preparations must take into account these multiple factors in order to maximize performance during the race.
As NASCAR embarks on this new chapter in Mexico City, it presents an exciting opportunity for both the teams and fans, showcasing the sport’s adaptability to unique racing environments. With the race engineers’ innovative approaches, one can look forward to a captivating race that highlights not just speed, but also the strategic engineering behind the scenes.