Q: What Is the Difference Between the Rotary Engine and a Piston Engine?

asked by on

What is the difference between the rotary engine and a piston engine?

The rotary-style (wankel) engine and piston-style engine are two totally different things, like a boat and a submarine.

The only company that uses rotary-style engines is Mazda; they used it in the Mazda RX-7 and Mazda RX-8 (both are discounted). The rotary engine was a compromise from a family of car engines derived from experiments in the early 1960s by Felix Wankel, a German engineer. Over the years, the displacement has been increased and a turbo was installed to make it faster and to gear it toward car enthusiasts. Wankel engines can be classified by their geometric size in terms of radius (rotor center to tip distance, also the median stator radius), depth (rotor thickness), and offset (crank throw and eccentricity). These conditions function similarly to the internal measurements of a regular piston-style engine’s displacement. Mazda rotary engines have a reputation for being relatively small and powerful, at the expense of poor fuel efficiency. They have been modified over the years to try to accommodate today’s emission standards, but to no avail.

The first commercially successful internal combustion piston engine was created around 1859 and the first modern internal combustion engine was created in 1864. This style engine has been in use in all facets of automotive and aircraft and marine. The piston-style engine has been modified by every car manufacturer in the world trying to make it lighter, cheaper, and more fuel efficient, even though all the basics of the piston-style engine are the same. A crankshaft is connected to either 3, 4, 6, 8, 10, or 12 pistons.

The piston-style engines are bigger and more costly to make and reengineer to suit today’s demands. All in all, the piston-style engines work better than the rotary engine in the vehicles we drive today due to weight and driver demands. However, the rotary engine does have some great advantages over the piston-style engine; it can rev up to or over 14,000 rpm (revolutions per minute) versus the 6,000 rpm maximum of a piston-style engine, which means it can be more useful in racing applications.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. What Is the Difference Between the Rotary Engine and a Piston Engine?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Engine makes metal-to-metal noise on a 2012 Ford Taurus SEL 3.5

If you are talking about engine noise, that means that the engine is on its way out. That generally means that the bearings on the crank are worn and that the pistons are making the clunking around. Because, instead of...

Q: Car shut off and remained unresponsive since then - 2010 Mercedes-Benz S400 Hybrid

Hello. The PCM is a potential cause of the problem that you are experiencing. The PCM is the main computer for the car and could be malfunctioning. There could also be a problem with the electric motor of the hybrid...

Q: Engine cut while driving, now dont crank.Cant turn it with hand.

Of course, first confirm that the plugs are correct for the engine. The wrong plugs, and/or missing crush washers, can cause interference with the piston. If the plugs are correct, the cause of the mechanical interference can sometimes only be...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.