Mazda RX-8 Renesis Rotary Engine
Published: 3rd June 2003
The engine itself has been redeveloped for greater power and reliability. It now features a side-intake, side-exhaust layout, with the exhaust ports moved to the side housing of the rotor chamber. This allows the size of the ports to be freely set, resulting in an expanded air-intake port area – 30% larger than in conventional rotary engines – greatly improving intake resistance and contributing to the high power development.
In addition, the adoption of dual exhaust ports for each chamber achieves twice the port area of conventional designs and also allows exhaust port timing to be delayed for increased thermal efficiency in the expansion process. Unburned hydrocarbons are retained for combustion in the next cycle, which greatly reduces emissions. A three-stage induction system, featuring shutter valves at the intake ports of each rotor, utilise the incoming air’s dynamic charge effect and improve filling efficiency, while twin electronic throttles precisely and flexibly control the valve operation. Furthermore, a wet-sump lubrication system with oil-pan height just half that of conventional designs also reduce engine size and weight.
The Mazda RX-8 is one of the most exciting cars to go on sale in
the UK market this year. With an on sale date during September this
car is sure to be in great demand.
