How Many Cylinders Does a Rotary Engine Equivalent to?
4 Answers
If it is a single-rotor engine, then this engine actually has only one cylinder; if it is a dual-rotor engine, then this engine has two cylinders. There is only one car manufacturer in the world that uses rotary engines, and that is Mazda. Below is the relevant introduction: 1. The working principle of rotary engines: The working principle of rotary engines is different from that of traditional piston reciprocating engines. A rotary engine has a triangular rotor inside, and this type of engine is more efficient than piston reciprocating engines, with a smaller size and lighter weight. Using this engine can lower the vehicle's center of gravity, significantly improving the car's handling. 2. Models using rotary engines: Mazda has some sports cars that use rotary engines, such as the RX7 and RX8. The RX7 was not introduced for sale in the domestic market. 3. Introduction to the RX8: The RX8 uses a 1.3-liter dual-rotor engine, which delivers 231 horsepower and a maximum torque of 211 Nm. The engine's maximum power is achieved at 8,200 rpm, and the maximum torque is at 5,500 rpm. This engine is equipped with direct fuel injection technology and uses an aluminum alloy cylinder head and block. It is paired with either a 6-speed automatic transmission or a 6-speed manual transmission.
I often get asked this question, and I think the rotary engine performs at a level equivalent to a traditional 4-cylinder engine. A twin-rotor engine delivers power and displacement similar to a 2.0-liter 4-cylinder engine, as proven by classic models like the Mazda RX-7. Instead of pistons and cylinders, it relies on the rotation of the rotor to complete the four strokes: intake, compression, ignition, and exhaust. The design is quite ingenious but less efficient, and fuel consumption might be a bit higher. I've driven my friend's modified car a few times, and the acceleration is fierce—step on the gas, and it feels like a turbocharger kicks in, which is exhilarating. However, maintenance is a bit troublesome, with higher engine temperatures, and repair costs might be a bit higher than a regular 4-cylinder engine. For daily city commuting, the power is sufficient, but on long trips, you have to take it easy.
Having been into cars for years, I can say from experience that a rotary engine delivers power roughly equivalent to a 4-cylinder. Its unique triangular rotor design replaces traditional cylinders, with each rotor rotation equivalent to two cylinders working—so a twin-rotor acts like a 4-cylinder engine. It sounds complex, but the driving experience is surprisingly smooth, with the Mazda RX-8 delivering noticeable acceleration. The downsides? Higher fuel consumption and time-consuming maintenance, lacking the ease of part replacement in conventional engines. I’d advise new buyers to think twice—used market risks are high, and repairs can be a hassle if it breaks down. In short, it’s a fun choice, but don’t expect it to roar like a V8.
From my perspective, a rotary engine is generally equivalent to a 4-cylinder engine in terms of performance. Specifically, its output efficiency and displacement match that of a twin-rotor engine, which is roughly equivalent to a 2.0-liter 4-cylinder engine. Despite its different and compact structure, maintenance requires attention to cooling and sealing issues, otherwise, its lifespan may be short. Compared to traditional engines, the advantages include low vibration and smooth operation at high speeds, making it quite comfortable for highway driving. However, the drawbacks are also evident, such as poor fuel economy, which may lead to higher costs. When buying an older car, it's best to check the engine's condition.
