Felix Wankel, a German engineer, worked for NSU (NSU Motorenwerke AG) and was the given the task of developing his “brainchild” rotary engine, an internal combustion powerplant that uses an eccentrically-turning rotor instead of reciprocating pistons. Although he had started development of a rotary engine as far back as 1924, it was in 1957 that he finally managed to get one running (the KKM 57) at the NSU research department. The engine showed great promise in that it was smooth, small, quiet and relatively simple, at least in concept. A number of companies – among them Rolls Royce, Curtiss-Wright, Norton, Suzuki, John Deere and GM – around the world attempted their own designs over the next few years, but none continued development.
No one, that is, except Toyo Kogyo, the little automotive company in Japan that would brand its cars Mazda. The company bought the patent rights from NSU in 1961, along with a prototype engine. That engine failed on the test stand within a few tens of hours, launching Toyo Kogyo on an intensive development program to solve the technical problems inherent in the rotary engine. Millions of dollars were spent on the metallurgical and machining aspects of the design, much of which was devoted to computer time to solve the “K Factor.”
And what is the K Factor? We’ll get to that in a moment, but first some theory.
Rotary engines use a triangular-shaped, rounded tip steel rotor that spins (eccentrically) inside a shaped housing. The shape scribed by the tips of the rotor form a geometric figure known as an epitrochoid. As the rotor moves inside the housing it comes very close to the walls of the epitrochoid, thus creating areas of compression. Valves and spark plugs can be situated in those areas, thereby creating combustion chambers. This powers the rotor, which was Felix Wankel’s great idea.
However, Toyo Kogyo found that there were two major problems to be overcome. The first was the form and materials needed for the seals on the sides and tips of the rotor. Without seals there would be no compression, of course, but the seals themselves need to travel with the rotor without causing wear in the housing, called “chatter marks.” Great amounts of time and engineering efforts were made to solve the sealing problem. To eliminate this phenomenon, a cross-hollow seal was developed by drilling small holes inside the metallic apex seal. This greatly improved the durability of the prototype engine, enabling it to complete 300 hours of continuous high-speed operation. Also in the initial stage of rotary engine development, engineers were faced with the further problem of engine oil leaking into the combustion chamber, causing excessive oil consumption. The team identified the oil seal as the cause of the problem, and developed an innovative Mazda-unique oil seal in conjunction with Nippon Piston Ring Co. and Nippon Oil Seal Co.
The second problem was the efficiency of the rotor itself. It was found that, as it turned, the radius of its rotation (from the center of the crankshaft attached to center of the rotor) relative to the eccentricity (the distance from the center of the rotor to the tip of the rotor) was critical to engine life and power output. Vast amounts of computer time were devoted to calculating the optimum radius-to-eccentricity ratio, or K Factor.
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Toyo Kogyo risked everything on the outcome, but it was worth it. On May 30 of 1967 they unveiled the first production rotary-engine Mazda Cosmo 110S, a little sports car that captured the hearts of enthusiasts with its 110-horsepower Type 10A engine. The Cosmo Sport recorded more than 3 million kilometers of road tests over six years, winning a number of races in the process.
Mazda was finally ready for the US market and, in 1970, introduced the R100. It was quickly followed by the RX-2, RX-3, RX-4 and RX-5 Cosmo along with its little Rotary Pickup truck. Owners loved the cars, but the oil crisis of 1973 and shifting needs of the buying public reflected the relatively poor fuel mileage of rotary engines. Solving the fuel economy and emissions problems of rotary engines took Mazda the remainder of the decade, but in 1979 the sports car world was completely shaken up with the arrival of the legendary RX-7.
The car was so successful that several subsequent generations followed in 1986 and 1993, culminating in the first turbocharged rotary engine RX-7, a highly sought-after collectible. Mazda’s rotary engine cars achieved over 100 professional sports car racing wins during these years, culminating in an overall win at the 1991 24-Hours of Le Mans and going into the history books as the first – and still the only – Japanese car company to ever win the famous race.
Mazda continued heavily into piston-engine products in the 1990s and early 2000s, but the rotary engine was far from forgotten. In 2003 they launched the RX-8, the first-of-its-kind 4-door pure sports car powered by its newest Renesis engine. Although it only displaced 1.3 liters and is the size of a toaster over, the 9,000 rpm engine developed 238 horsepower and 159 lb-ft of torque. Its sales remain brisk as the current model year marks 40 years of rotary engines for the company.
Where Mazda might take the rotary engine in the future is anyone’s guess, but it’s sure to be with us for many years to come. No other company ever succeeded with rotary engine design and engineering and no other company ever did so much with it. Rotary-powered Mazda cars are certain to hold a very significant place in automotive history.
A Quick Note From Our Founder –
Over the past few years I’ve taken a very special interest in helping people lose weight and live a healthier lifestyle. Please take a moment to read Brian Flatt’s incredible story and how he burned over 12 pounds of fat in 3 weeks by Working With Nature, Not Against It.
Did You Know That Your Body Is Stuck in “Fat Mode” for 20 Hours a Day?
Learn How New Research Can Unlock Your Hidden Fat-Burning Potential.
In America, we’ve achieved something incredible:
Absolute freedom from the dangers of nature.
Nature’s most vicious predators are no match for humans.
But one danger still haunts us, something that’s stuck with us from the natural world that we simply can’t fight off.
In fact, it’s killing more Americans than any other cause of death.
Here’s just a glimpse as what Americans are suffering through:
● Heart attacks and strokes that put an immediate end to the life of people we love. (If you’re walking around with extra fat on your body, you never know when these illnesses will strike.)
● Back and join pain that stops you from enjoying life, keeps you stuck on the couch, and ruins your mood from the moment you get out of bed.
● Plus diabetes, liver failure, sore muscles, arthritis, and more, costing thousands of dollars in prescription medication every year.
Even children are suffering the consequences.
My Daughter Was Thin, But She Was Suffering from My Weight.
When I was overweight, I thought, “you know, it’s not so bad. I can live with this.”
But then one day, my chest started to ache, and I thought I was having a heart attack.
Just at that moment, my daughter looked up at me with the most scared look I ever saw.
I knew I couldn’t leave her behind, so I decided to look into the real causes of my weight gain.
I Was Spending 20 Hours a Day Gaining Fat, Even if I Ate 3 Meals a Day.
I was shocked when I found out that our bodies can only be in one of two states.
Either we’re burning fat… or we’re gaining it. There’s no in-between.
And many Americans are unknowingly spending 20 hours a day stuck in the fat-gaining mode, especially if they’re overweight.
20 hours a day!
And the only time they’re actually burning fat… is when they’re asleep.
That’s when I realized that no matter how much exercise I did, no matter how healthy I was eating, it wouldn’t matter unless I could fix that problem.
I had to find a way to force my body into fat-burning mode for more than 4 hours a day.
Finally, I was lucky enough to stumble across a new system that works with nature’s big secret to keep my body in fat-burning mode for 12 hours a day or more… and I lost over 12 pounds in just 3 weeks!
I Burned Over 12 Pounds of Fat in 3 Weeks By Working With Nature, Not Against It.
Your body has a natural ability to burn fat.
In fact, you can burn a surprising amount of fat in just a few weeks with the right strategies.
So what are they?
Well, the plan I made works in 3 phases, and they’re incredibly easy to follow.
Basically, here’s how it works:
1. It forces your body into fat-burning mode for 3 times as long. By multiplying your fat-burning time, you make weight loss easy, even without difficult workouts.
2. Plus… it showed me how to make my work outs easier and actually improve my health. (As it turns out, many people are already doing the #1 exercise you need to burn fat!)
3. In Phase 2, I dropped over 1 pound per day, and I was pleasantly surprised as how easy it was to do.
At the end of 3 weeks, I had lost over 12 pounds of fat.
I kept it up and continued to lose more.
And yes, I looked amazing.
But what really mattered wasn’t the weight loss.
I had made a change for my daughter.
I’m Going to Live to Watch My Grandchildren Grow Up.
I may not be old enough to have grandchildren yet… but now, I’m not worried that I’m going to die before my daughter is ready to have kids.
We’ve really connected again, going out to the park and playing games like we used to. I can even go shopping all day long without getting aches and pains in my back!
So I shared these strategies with some of my friends who wanted to lose a little weight, and they were shocked at the results.
In fact, some of them were losing more weight than I did… up to 23 pounds in 3 weeks!
So my friends told their friends… who told their friends… and eventually, the secret got out.
People Started Offering Me Money for My 3 Week Diet.
I couldn’t believe it when complete strangers started emailing me, asking for my diet.
I had no idea it was going to become such a big deal!
That’s when I realized that I had to get this out there for anyone who wanted to start burning fat and looking their best.
(Who am I to hide this from other people?)
So I decided to put together all the information I had on this strategy and put it online.
The only problem… is that it costs a lot of money to do this.
I was a little overwhelmed by how much I had to pay to put together a website and package it all up in a nice little ebook.
So yes, I have to charge people for these strategies.
But when people are losing 12 to 23 pounds per week, I’m not hearing any complaints!
I’m Going to Save You $20 on These Fat-Burning Secrets.
When I showed my website to a friend, he told me I was crazy for making my book so cheap.
“You should be charging twice as much, at least. I’ve seen books like yours for $60 or more.”
He works in marketing, so he thinks everything should be expensive. (Sorry, Dave.)
I just couldn’t do that. I really wanted people to be able to afford this book and use it to change their lives.
So I did the math and figured out exactly what I have to charge to get my money back on this whole thing, and that’s how I chose the price.
If you can help me cover my costs, I’m more than happy to give you these secrets at the bare minimum price.
So click this link to get full access to these fat-burning tricks, and I promise… no, I guarantee… you will lose 12 to 23 pounds in 3 weeks!
Creator of The 3 Week Diet & Weight Loss Consultant