Dennis+Lima

Dennis Lima's Senior Capstone Project The Wankel Rotary Engine

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The Rotary Engine

[|Presentation Powerpoint]
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Annotated Bibliography
Dark, Harris Edward. __The Wankel Rotary Engine__. the book is about the man who invented this engine, dr felix wankel and the design of the engine and how it works. its a good book but i already knew everything about the engine before i read the book. its not that relevant because i already know everything about this engine but it is accurate.

Moffat, Allen. "A CONTROVERSIAL DRIVER IN A CONTROVERSIAL CAR?" __//MOTOR//__ 11 Aug. 2010. //General Reference Center Gold//. Web. 8 Mar. 2011.

Journal
2/12/11 researched 2 rotor engines. The 13B REW. I have been studying this engine for years. It is both innovative and genius in its design- a work of art.

2/13/11 researched 3 rotor engine and looked up some videos of rx7s with 3 rotors sounds wild.

2/15/11 studied the 4 rotor engine and watched videos of rx-7s and 787bs the engine sounds even wilder.

2/27 I read an article on rotary tuning. I f a computer is connected to an RX-7 the air fuel ratio can be adjusted as well as the boost needed to make the turbo run.

3/1: I researched the turbo charger setup on a rotary engine. In the FD generation RX-7 sequential turbo sytems are used. A small turbo and a bigger turbo replace the twin turbo setup. This seems to work much better in bringing up the horse power.

3/7: I looked at modified RX-7's. On You Tube there are millions of videos on RX-7's. People add after market air boxes and after market exhausts, bigger turbos etc. A lot of people use turbo timers. When the car is shut off, the turbo timer beeps and the car keeps running to cool the turbos down. In an inter cooled car, the inner cooler will cool the turbos when it is just idling instead of making them hotter.

4/1: I went to my uncles and grabbed some rotary parts to bring in. i grabbed a rotor housing and a rotor. I plan to demonstrate how it works and explain why they have to be rebuilt every thirty thousand miles.

4/7: I learned why rotary engines are not economical. Because they have to be rebuilt every thirty thousand miles and not a lot of people are able to do this, hiring a mechanic to perform the work can be costly.

The Research Paper
Dennis Lima English 11/12 Senior Capstone Project The Research Paper The rotary engine had been attempted countless times by people all over the world since the 16th century. At the age of seventeen, Felix Wankel had a dream in the summer of 1919 which led to the idea of the rotary engine. In the dream, he went to a concert in his own handmade car. He bragged, "my car has a new type of engine: a half-turbine half-reciprocated engine. I invented it!" ( [] ). The description half-turbine, half-reciprocated means that two rotors spin internally. A turbine is basically two triangles spinning inside an oval-like housing connected with an eccentric shaft. Reciprocated describes the spinning rotation of the rotors inside the housing. The engine has no pistons and is considerably smaller in size. Although the rotary engine failed to gain widespread popularity in comparison to the four-stroke piston engine, from its origins through its emergence in the America market, the engine is more economical and produced greater horsepower for its size in comparison to its competitors. Who would have thought to put two triangles in an oval and make them spin? The rotary engine has only 3 moving parts. These parts are the eccentric shaft and the 2 rotors. The rotors are rounded triangles that spin in an oval-shaped housing. The displacement is 1.3 liters (each rotor displaces 654 cubic centimeters) and it produces 280 horsepower which is remarkable for its size. Some would call it efficient. Though it gets the fuel economy of a v6, it outputs the power of a v8 with an engine comparable to a 4 cylinder in size. The Wankel rotary engine has been used in many different cars made by Mazda including the Cosmo, the Cosmo sport and the RX-7. With the onset of the automobiles through the 1970's, piston engines resulted in lost power, poor performance and reduced fuel economy. Another significant concern of the time period was the gasoline shortage. During this time, drivers would often be faced with "out of gas" signs at service stops causing panic throughout much of America, manufactures often de-tuned their engines dramatically to save fuel for instance a v8 that would normally be making 340 horsepower would make around 180. Indirectly resulting, manufacturers in Toyo, Kogyo, Hiroshima, began producing the Mazda emphasizing its small, inexpensive Wankel rotary engine. Within a few years, the Mazda name was recognized in American markets. By 1973, dealers were selling out of Mazdas as soon as they hit the lots. With such widespread demand, the American production corporation for Mazda focused their efforts on the marketing of the Wankel rotary engine in contrast to the traditional four cylinder engine. The Wankel rotary engine has impacted automobile racing and brought Mazda significant success in the racing industry. Wankel-engine cars in two-rotor, three-rotor, and four-rotor forms, and piston-engine models have been used in competitor cars. More Mazdas are raced every week than any other car brand on international racetracks. Mazda began competing in the auto industry in 1968 with the Mazda Cosmo Sport. The first racing victory by a Wankel- engined car in the United States was in 1973, when [|Pat Bedard] won an [|IMSA RS] race at [|Lime Rock Park] in a [|Mazda RX-2] (Sherman, 76). Mazda has run many racing cars especially the RX-7, 787B and the RX-8 all with rotary engines. The 787B dominated its first race and was later banned because there was no competition for the car. It used a four rotor engine and beat out everything on the track.




 * || In 1991, Mazda’s 787 raced in the [|World Sportscar Championship], [|All Japan Sports Prototype Championship], as well as the [|24 Hours of Le Man]. The 787s were the last [|Wankel rotary-powered] racing cars to compete in the World and Japanese championships. ||

The RX-7 had a 13b-REW which is a 2 rotor engine. Some of them even have a 3 rotor engine called the 20b-REW. This engine produces around 500 horsepower with minor modifications such as a bigger turbo and some ECU tuning (the onboard computer for the engine.) The 787-B used a 4 rotor setup called the 26B-REW it produces over 700 horsepower and sounds like nothing I’ve ever heard. Some people have hand built these for street rx-7s and some tuning companies such as Scoot Sports. But Mazda has not given up on the development of the Wankel rotary engine. A new breakthrough has been made with an engine featuring side ports for both intake and exhaust, allowing better breathing and leaving more freedom in the selection of the timing diagram. This has gone a long way to improve both fuel economy and specific power. Prototype engines are now being further developed, and in two or three years time, the Hiroshima-based company could well startle the world with a much more fuel-efficient and less expensive rotary engine with an exceptionally high power-to-weight ratio.

**Works Cited**

"The Rotary Club", Don Sherman, //[|Automobile Magazine]//, February 2008, pp