With the discontinuation of the Mazda RX8 last decade, the Wankel engine in now facing certain doom, but, why is the Rotary engine dead?
The Rotary Wankel engine seems to be the automotive equivalent of Icarus, who flew too close to the sun; its glorious innovative prowess seems to be its downfall and subsequent demise.
Much like the aforementioned Greek Mythology character, the Rotary gets too hot, and it burns itself while ascending to the heavens. Of course, we’re referring to its astronomically high redline.
So technically speaking, why is the rotary engine dead?
Well, a Wankel purposely burn oil, because lubricant is injected into the rotor housing to lubricate the apex seals, this prevents premature seal wear and warping, which results in compression loss.
Another issue is the fact that this types of engine runs a rich air-to-fuel ratio to compensate for the fact that the combustion chamber “moves away” i.e. expands, thus making it harder to ignite the full fuel discharge.
These two particular issues combined with many others cause the Rotary engine to fail emission standards everywhere, which is why it has been phased out in recent years.
A more technical explanation can be seen in the video below.