The Wankel engine, the odd ball engine that bucked conventional wisdom is dead. We’ve known this ever since the RX-8 went out of production. Rotary engines have a lot of advantages over their piston driven friends. They are capable of making huge power in a small package. They have an insanely high redline. Want to increase displacement? Of course you do, just slap how many more rotars you require, get a drive shaft and ancillary to match and away you go. It isn’t extremely easy but it is a lot easier than it is in traditional engines. They are capable of making huge power in a small package.
Unfortunately there are a lot of disadvantages to Rotary Engines, chiefly they burn through oil. Secondly they tend to eat main seals. If you drive them like an enthusiast (high revs) you can find yourself requiring a new seal in a shockingly short amount of time. The fix to this is running premix (gas and oil mixed together), which is a huge pain in the ass. There are more nails in the Rotary coffin, but instead of droning on about it, I suggest you just watch the video below. Here a man MUCH smarter than I am explains the top 4 reasons the Rotary Engine is dead.
Now there are abundant rumors that the Wankel will rise from the ashes and make a comeback. Hopefully in some form of RX, sporting twin turbos. It may be flawed but the world is a better place when you can buy a brand new car with rotary power.
Source: Engineering Explained