Toyota GR Yaris (GXPA16) Rally1 with Katsuta: single turbo setup

Toyota GR Yaris: mechanical breakdown

Katsuta in the Rally1 GR Yaris

An 8-second clip titled as the GR Yaris Rally1 driven by Takamoto Katsuta in the WRC. The caption says WRC fans are sleeping on him. It names no event, stage or modification, so the clip is about the driver and the Rally1 car, not the GXPA16 road car covered on this page.

One turbo and an air-to-air intercooler

The G16E-GTS gets its 257 hp and 360 Nm from 1618 cc through a single turbocharger. That turbo feeds an air-to-air intercooler, which cools the charge using airflow over the core and has no coolant circuit to saturate. Its limit is ambient temperature. In hot conditions on track the intake air heats up, and the car responds with a power reduction. The turbo is also part of the sound: turbo and wastegate noises are audible, and an aftermarket intake or downpipe makes them more obvious because there is less between the turbine and the outside air.

Intercooler, remap and downpipe trade-offs

Heat soak is the usual reason owners fit an upgraded intercooler. It lowers intake temperatures and keeps power consistent on track. The trade-off is cost, and more turbo lag if the core is oversized. An ECU remap gives large gains in power and torque on the stock turbo, with higher engine stress and possible warranty problems. A downpipe and exhaust make the car louder and support higher-boost tunes. Emissions and noise legality concerns come with it, and drone.