This inlet duct performance car part is much larger than stock with a close fit to the front bumper and airbox to ensure that the heat from the engine causes minimal effect.

During testing on track days, the original duct caused inlet air temperatures to be heavily influenced by heat soak and fluctuated dramatically. Meanwhile the Forge inlet duct kept the inlet air temperatures not only reduced but at a more consistent temperature. A reduced consistent temperature is of great importance because any high temperature peaks will cause the ECU to retard the ignition and reduce the power you have available. The Forge inlet duct design incorporates a free-flowing path to both the upper and lower opening of the airbox, whereas the stock design has no flow management to the lower opening and the upper is small and not fully sealed. It is worth understanding that the lower opening is of far greater importance to the performance of your Yaris GR. There is a vacuum operated flap which is activated when under full throttle conditions, therefore the Forge Motorsport Inlet Duct ensures that your Yaris is getting colder directed air when the engine needs it the most.