The dual vvt-i engine toyota corolla is a testament to Toyota’s commitment to innovation, bringing an optimized driving experience to a compact sedan. VVT-i technology is designed to adjust the timing of the intake and exhaust valves, improving fuel efficiency and performance. With the addition of "dual" VVT-i, both valve timings are independently adjusted to further enhance engine output, whether you’re cruising on the highway or accelerating from a stop.