The 1NR, 2NR, 3NR, 4NR, 5NR, 6NR, and 7NR engines have Dual VVT-i standard and the 8NR engine has VVT-iW, enabling it to operate in the Otto cycle as well as a modified-Atkinson cycle to improve thermal efficiency.
Mesin 1NR, 2NR, 3NR, 4NR, 5NR, 6NR, dan 7NR memiliki Dual VVT-i standar dan mesin 8NR memiliki VVT-IW, memungkinkan untuk beroperasi di Otto cycle serta Atkinson cycle yang dimodifikasi, memaksimalkan efisiensi termal.