Having spent a single season using year-old Ferrari power units, the Toro Rosso STR12 for the 2017 F1 season benefitted from up-to-date hardware. The team rejoined Renault, aligning themselves once more with parent team Red Bull.
Their fortunes during the previous season had been shaped by the growing gap between them and their rivals in engine performance. However the aerodynamic performance of the STR12’s predecessor had been a major strength. Designer James Key remained at the helm for the new season.