Mazda to further refine Wankel rotary engine for more efficiency?
Mazda's Wankel rotary engine has always been unique in the automotive landscape as a mass-produced internal combustion engine that eschews such unsightly items as pistons, valves and camshafts. The Wankel packs lots of power into a very small package, but one thing it's never been is fuel efficient, despite its relatively meager 1.3-liters of displacement. It seems the Japanese automaker is working hard to change that reputation with the next generation of the RX series.
Like the classic 13B engine that the current Renesis is still based on, the new 16X would use two rotors, though enlarged to 800cc each for a total of 1.6 liters. Despite the increase in displacement, Mazda hopes to increase fuel economy and reduce emissions by 20 percent.
Other efficiency improvements are planned as well, including a dual-clutch transmission and a significant weight savings over the current RX-8, which isn't exactly a porker as it is. Supposedly, the new rotary would be available in both a two-door, two-seat RX-7 and a larger, four-seat RX-9 variants.
[Source: Inside Line]
Reader Comments (Page 1 of 1)
pditty 3:00PM (2/13/2009)
I am all for lightweight, sporty, unusual cars. I even own a Mazda 3 (wife pushed hard for an RX8)
But Mazda needs to give it up... an unreliable, underpowered car that uses a ton of premium fuel and burns a crap lot of oil???
The Mazda 3 can be had with more power AND more efficiency (turbo).
Mazda has "fixed" the problems inherent in the rotary (fuel economy, emissions, reliability) in each generation of the motor since 1980 and still hasn't actually done what they've promised.
Give it up, everyone else has.
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Kitko 8:50PM (2/15/2009)
There's lots of misconceptions about rotary...
A) They are reliable. Almost all problems result from people abusing the engine - either after being lured by "yeah, it revs until 9000" or just not being able to drive. And that's 80% of population.
B) 13mpg can result only when the car is being driven VERY hard or by someone from the 80% of the population. Drive ANY 230 HP car like that and you'd get 13mpg as well.
C) A German car magazine tested the RX-8 - during the test, Mazda consumed LESS oil than a comparable piston-engined car.
The Rotary engine is different. Learn to drive it properly, or just shut up.
It's same with diesel. You can't drive diesel car like a petrol powered model.
pditty 3:05PM (2/13/2009)
Also,I don't see "hydrogen" anywhere near "rotary" in this article, so just wondering what the "green" connection is with this article.
20% better economy? on a 1.3 liter that gets 13mpg real world (for many people with heavy feet).... ?
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Rain 3:32PM (2/13/2009)
I can see this thread going up in flames rather quickly.
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Yikes 3:42PM (2/13/2009)
If the Mazda Rotary is so great(small light weight, powerful) why hasn't it ever been in the Miata/MX-5?
Rain 4:00AM (2/14/2009)
Yikes,Good point.
Actually I'll have to go out on a limb for this besides the points You brought up,small,lightweight.
The Rotary is a Thirsty engine and it has been dirty.
When it was introduced inside the RX-7SA-FA with the version 12 A RE to the United States it fell under the Gas Guzzler tax of the day,despite the cars weight at just over a ton it only got on average 12-14 MPG and with oil injection,the emissions were horrendous.
The later 1st Gen RX-7 FA came equipped with Fuel Injection on the 13 B RE,the 13 B was in testing upon the cars release but the earlier 12 A got slightly better mileage so Mazda used it instead.
The 13 B was fitted with the fuel injection if memory serves in 1983
and this made the car much better to drive and slightly decreased the emissions and slightly raised the MPG though the engine made from memory again about 30 more horse then the RX-2,RX-3,RX-7 SA's.But still the engine relied on oil injection to keep the seals and crank torus lubricated.
A variation of the 13 B RE is used today in the RX8(Gasoline and Hydrogen) and the concept Furai race car.
Here is a link to a much more detailed history of the rotary,for Your enjoyment:
http://www.turborx7.com/historyre.htm
The MX-5 and the later MX5 Miata have a history of being adapted to Rotary Power by enthusiast,Enthusiast do not have to adhere to emissions regulations in the same way that manufacturers do.
Here is a nice professional conversion,though He is certainly not helping the environment here:
http://www.youtube.com/watch?v=cASvdEm_9Ss
The next phase of the REW has already begun its called the 16 series after a total re-design
from the ground up,new technologies will further increase the efficiency and reduce the emission levels while increasing horsepower and torque for even more Zoom-Zoom.
Here is a peek into the next series the 16x:
http://www.mazda.com/mazdaspirit/rotary/16x/
Some fun facts:
Mazda is used in more sanctioned automotive sporting events than any other marques in the USA to this day,the reliability of this simple engine with low maintenance make it a superb choice for competition on a budget.
The RX-7 was born on the Laguna-Seca race way as a by product of the improvements in performance by American enthusiasts modifying the RX-2's and RX-3's,The California President of Mazda sales kept notes in a notebook which He forwarded to Hiroshima and was later put in charge of the production of the upcoming Savannah RX-7 project.
The Mazda 787b (20b 4 rotor) is the only Japanese LMP car to ever win at Le mans(24 hours) in the prototype class.
Thats an impressive history for a weird little engine.
I hope it does find a home in forthcoming Miata's,that would be an enthusiast's dream.
Thanks!
Yikes 10:29AM (2/14/2009)
THanks for all that info.
Jeremy Korzeniewski 3:53PM (2/13/2009)
If Mazda is going to continue pressing forward with the rotary engine, and all signs point in that direction, increasing its efficiency is a positive development and is therefore newsworthy...
Plus, if there is ever a chance of a hydrogen-powered rotary, it will come from Mazda and we therefore have at least a passing interest in reporting on the Wankel's continued development.
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alexacoon 7:09PM (2/13/2009)
I would really expect that you wouldn't be fooled into believing this motor displaces 1.3 litres; thats incorrect as thats the displacement for one side of each three sided rotor. Since this motor effectively has 6 "cylinders" not 2 it truly displaces 3.6 litres and has the power/mileage figures you would expect.
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MikeW 4:33PM (2/14/2009)
No, 2.6 liters. Look at the duration of the stroke
[but I don't want to ruin it for wankel owners who get insurance benefits from having a small engine 4 door car ;) ]
Yes 2 a rotor is like 6 cylinders, 3 rotor like 9 cylinders, 4 like 12.
jharlan 10:03PM (2/14/2009)
Maybe they need to try a 500cc Wankel. If they can't get 30 MPG with that thing, Then it won't sell enough to cover the R & D.
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rotaryrocket 1:40AM (3/07/2009)
Why is it that whenever ANYTHING about rotaries is posted on the internet, every piston a**hat feels the need to post every lie & misconception they've ever heard?
Oil consumption: There are so many piston engines that burn as much, or more oil than rotaries. My '88 turbo 13b sips only about 1 quart every 2-3000 miles with plenty spirited driving.
Mileage: The RX-8 is rated at 22 hwy. My 300hp modified '88 RX7 turbo gets 23 hwy, and was rated at exactly that in stock form. If you assume the 16X will get 20% better fuel economy, then that will be about 26-27 hwy & around 300hp (with the added displacement). And let me remind everyone...SPORTS CARS ARE NEVER BOUGHT FOR FUEL ECONOMY! If you want economy buy a honda and have fun crawling up hills.
Reliability: Inexperienced piston-heads have ruined the reputation of the rotary. It is far more sensitive to knock/detonation than piston engines, so when someone tunes one incorrectly, it is much easier to have a catastrophic failure. This is particularly a problem with turbocharged rotaries, since many people that has no business modifying the engine screwed it up. Do it right and the engine will perform beautifully.
Longevity: There's 180k on my engine, and I know of many RX7s with 200k or more. One car in particular has 261k and still runs as strong as day 1. Proper lubrication of the seals (oil and fuel), proper air/fuel ratios, and low engine bay temps ensure that they last a very long time.
Bottom line: If the 16X can improve bottom-end torque, peak power, mileage and emissions by 20%, it will put the N/A rotary in place to give any of the high output V6s (and some V8s: Ford 4.6) a run for their money.
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luisigor 3:00PM (8/13/2009)
How are you supposed to drive an RX8? I was planning on buying one, but I have known about too many issues with car engine. The oil Mazda dealers put in the car for example, It breaks down, thus it does not lubricate and Kabooom... Fucked up engine. They change the engine but put the same 5w-20 oil... again.
Dalancroft 1:59PM (6/09/2009)
Sure would like to see a rotary in the MX-5. Would help it compete with the Solstice/Sky duo, and given its small size and light weight it could be placed in a serious, no-holds-barred sports car weighing perhaps 300-500 lbs. less than its piston-powered brethren. Sort of like the approach taken by Lotus. Now THAT would be a car to watch!
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thedoc 9:09PM (8/14/2009)
Hello Everyone
Just a few comments here about the RX 7. I own a 1981 Mazda RX 7 for 10 years now, it was used when I purchased it, it is a stock 12A engine with (now well over 200 K) on it, the engine has never been apart and I rarely need to even touch it, it just works perfectly year after year. Also...I Drag Race it regularly...often Exceeding the red line on the tach, drop the clutch at 3k rpm off the line, drive it daily as well and abuse it a lot and it just keep purring along. I imagine someday it will fail but not anytime soon. As a closing note... it will still do the 1/4 mile according to the factory time. Not bad for a little weird engine eh !
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