Robert Mitchell told about the sad and tragic story of a fifth-to-second gear downshift in a Toyota GR Yaris previous week.
The driver intended to put the stick-shift Toyota Yaris to fourth gear when accidentally he put the car to second on the Nürburgring racecourse in Germany. The wrong shift resulted in a mechanical overrev, though fortunately, he applied the clutch back again just in time while it was happening. It didn’t show any signs of failure right after, and Mitchell scored a few more laps, but sadly, the car died on the lap the next day.
Apex decided to take off the engine, as the wrong-shift resulted in voiding the Toyota’s warranty, and the damage is clear with the valve cover removed. The overrev resulted in one of the intake valves floating, and with the piston pressuring the valve, the rocker arm that forced on the valve spring collapsed. This stuck open the valve resulting in the loss of the cylinder’s compression.
Taking everything into account, the damage isn’t that bad, thanks to the clutch’s timely application, which allowed the engine to reach its normal operating speed right away. If the clutch weren’t applied on time, it would have cost in losing the compression for at least another two of the cylinders, and the engine would have been full of metal debris.
Getting the car back to run won’t be an easy feat because the GR Yaris is a new model. Toyota hasn’t made the service manuals available for the car yet, and so is for its parts. Making that Apex would need assistance from Toyota itself, or the car would sit idle for quite some time now.
The perfect reminder that no wonder the technology has come so far, still a mechanical overrev could not be prevented and would cost in the breakage of the engine’s internal parts. We all have made this mistake at some point. However, doing it while revving the car to its max on a track could cost more than doing it while cruising around. Mitchel made a simple, honest mistake with extra-ordinary consequences, given his high speed.
