Toyota’s G16E-GTS engine, as found in the GR Yaris and GR Corolla models, is already a potent unit. However, storied Japanese tuning house HKS has released details of an engine kit intended to push its performance even further.
Key to the development is the implementation of a pre-chamber ignition system. HKS states that the pre-chamber, which appears to be a passive system, is produced from material with high thermal conductivity, while the chamber itself is heat shielded.
In order to survive higher combustion temperatures, the valve seats and valve guides are also made from phosphor bronze, while any sharp edges in the chamber have been removed and mirror polished, presumably in an effort to reduce the chances of pre-ignition.
To complement the pre-chamber system, a high-swirl port profile has also been created, along with a high compression piston with a crown profile intended to encourage swirl. Furthermore, the piston crown is nickel coated to improve knock resistance and a two-layer, molybdenum coating has been applied to the skirts to reduce friction.
The capacity of the engine is increased from 1,618cc to 1,746cc, thanks to a 88.0mm bore and 95.7mm stroke.