Development of Sequential Twin Turbo System for Rotary Engine

In today's automobile markets, there has been a strong and growing demand for higher output and better fuel economy engines. In order to improve rotary engines to satisfy this market demand, Mazda has devoted much effort to turbocharging system development and achieved the Sequential Twin Turbo System, which overcame the problems typical of conventional turbocharging systems; insufficient torque at low engine speeds and turbo lag. This system, which has two turbocharging units that operate in accordance with engine speeds (one unit at low engine speeds and both units at high engine speeds), features;

1. (1)
   Compact and reliable turbo operation control system
2. (2)
   Reduced temporary torque drop occurring when the second turbo starts

With this new turbo system, Mazda's rotary engines have achieved an output performance equivalent to large displacement engines and smooth driving performance, while maintaining their light weight, compact size and better fuel economy.