A Wankel engine is also known as a Rotary engine and it runs via internal combustion. This engine isn’t in common usage these days. In fact, Mazda built its final one of these engines back in 2012.
To help you get the inside scoop on this engine type, we’ve compiled a detailed article which includes plenty of pertinent facts, including exactly how this engine works and its primary pros and cons.
First, let’s review some basic facts about this motor design. We’ll talk about what makes it different from a typical piston-based engine, and also discuss the person who invented this motor, way back in 1957.
Wankel Engine – Basic Facts
This type of motor features a 4-stroke cycle which happens inside of a mobile combustion chamber. This chamber is situated between an ovoid housing system and a rotor which resembles a flat-sided triangle.
Created by Felix Wankel, who was an engineer of German nationality, this rotary motor offers distinct advantages and disadvantages to users, so it’s better for some applications than for others…
Felix Wankel was an engineer and he was born in the summer of 1902. Although he never earned a formal engineering degree, he started his own small-scale engineering company and went on to invent a host of products, including his Wankel rotary engine and components for this type of engine.
Pros and Cons of the Wankel style Engine
The chief “pro” of this form of engine is that it doesn’t contain as many parts as comparable engines. In particular, it has fewer moving parts. Since it doesn’t need valves or valve-trains and it doesn’t have connecting rods, a crank-shaft, or balance weights for a crank-shaft, it’s simpler in terms of components, and this is a good thing for some users.
Most engines are fairly high-maintenance. This motor dazzled in-the-know engineers and mechanics, as it offered hope of easier maintenance. Since Felix Wankel never even earned a driver’s license, it’s rather ironic that his design found a home in a range of sporty cars. Wankel won awards for his career achievements over the years – however, he will always be best known as the creator of this unique engine, which was very different than other engine styles of his time.
A couple of moving parts will be all that it takes to get this type of motor going and these are a rotor and an eccentric shaft. As well, this unit won’t need a timing belt or a rocker.
Fewer parts mean fewer parts replacements and less maintenance. This may be very cost-effective.
Another “pro” of this form of engine is that it’s not prone to shutting down suddenly, as some engines are. Therefore, it’s a dependable choice. Even when this engine heats up too much, it should continue to function without suffering from “sudden death”. Piston engines are very prone to shutting down completely when they overheat or experience other performance issues.
One of the advantages of this engine type for racing is that it has an excellent power-to-weight ratio. That means that it puts out a lot of horsepower for how much it weighs. An engine of this type can be modified for more power by adding a turbo charger, porting the intake and exhaust, or both.
One well-known drawback of this engine is its subpar sealing. Since the rotor of this machine must have seals which attach to the ends of its chambers, piston rings are needed in order to get the job done. However, even with piston rings helping out, sealing is typically not flawless.
When sealing isn’t flawless or very good, an engine’s lifespan may be shortened. In other cases, the engine may not be as efficient as it should be, due to ineffective sealing. For this reason, some people prefer to use piston engines, as they don’t have this particular disadvantage.
In addition, combustion may not be as good as it is in other forms of combustion engines. This is due to the larger size of a Wankel type engine’s combustion chamber, which tends to prevent a flame from arriving at the chamber’s “trailing” side, particularly which the motor is being run at higher speeds.
One of the cons that we care about a lot is that wankels tend to get poor gas mileage. The fuel economy of a piston engine of the same displacement is much better than that of a rotary(wankel) engine.
More Wankel Engine Facts
Mazda is an example of a famous automotive manufacturing firm which has created cars with Wankel engines. For example, Mazda’s RX-7 and RX-8 both featured this design. While you’ll have difficulty finding a new car with a Wankel engine, you’ll be able to find plenty of used vehicles which do feature this form of motor.
This engine was invented in the late 1950s, so it’s a relic of another time. However, this doesn’t really explain why it’s not a popular choice today, as other types of engines were also created during this time period (and are still in usage now).
If you’re curious, you should be able to locate cars with these engines at classified ad sites and used car dealerships. Since these engines are special, it’s important to understand the pros and cons of choosing a vehicle with this form of motor.
Ultimately, the cons of this motor, which we outlined above, go a long way to explaining why it’s not a common choice these days and why automotive companies have stopped using this engine type in their designs. Apparently, the cons of these engines outweigh their benefits.
In particular, the weak sealing system of the Wankel engine may be the reason why other forms of engines are now preferred. Engine efficiency requires effective sealing and the Wankel just doesn’t deliver the tight sealing which is needed in order to support a truly efficient engine while it is in operation.
However, from a mechanical standpoint, they are interesting motors which have some unique features, and they did appear in many famous car models over the decades.
There are plenty of cars out there which have these engines. In addition, the World Wide Web features lots of pictures of these engines. You may also find informative videos about Wankel engines on YouTube and other video sharing websites. Car buffs may discuss models which have these engines at message boards and social media groups, so there should be lots of places to find tips on how to repair and maintain this form of motor.
Wankel motors are important pieces of history and they served their purpose for decades.