multiple rotors
Joined: May 2002
Posts: 5,972
Likes: 37
From: Ottawa, Soviet Canuckistan
In case you haven't sensed the sarcasm from these goofs, yeah it's not only been DONE, but it's very well documented.
A 3-rotor engine is called the 20b. Mazda made this engine for the Cosmo, which was never sold in the US or Canada, so we don't hear of it much except on here. Other people have sandwiched together 13b engines with custom e-shafts to make their own 3 and 4-rotor engines.
Anything but a stock 20b cosmo is a HUGE custom job. The engine itself is hard enough to custom build, not to mention mounting it properly in the car.
Do a search (if it allows terms that small). You'll be pelted with thousands of threads, some useful, some useless. You'll find TONS of info. Recently there was a post about mounting a 20b into a first gen by cutting the firewall and whatnot.
Spend some time in the FAQ at the top of the page, visit www.rotaryengineillustrated.com and www.howstuffworks.com (search rotary engine) to learn more about the engine. Then head to the main www.rx7club.com page and look for the performance section that does alot of 20b stuff. You'll find a wealth of information.
And to bait your breath, there's a 4-rotor engine out there that's custom built, it's been nicknamed the 26a.
Have fun
Jon
A 3-rotor engine is called the 20b. Mazda made this engine for the Cosmo, which was never sold in the US or Canada, so we don't hear of it much except on here. Other people have sandwiched together 13b engines with custom e-shafts to make their own 3 and 4-rotor engines.
Anything but a stock 20b cosmo is a HUGE custom job. The engine itself is hard enough to custom build, not to mention mounting it properly in the car.
Do a search (if it allows terms that small). You'll be pelted with thousands of threads, some useful, some useless. You'll find TONS of info. Recently there was a post about mounting a 20b into a first gen by cutting the firewall and whatnot.
Spend some time in the FAQ at the top of the page, visit www.rotaryengineillustrated.com and www.howstuffworks.com (search rotary engine) to learn more about the engine. Then head to the main www.rx7club.com page and look for the performance section that does alot of 20b stuff. You'll find a wealth of information.
And to bait your breath, there's a 4-rotor engine out there that's custom built, it's been nicknamed the 26a.
Have fun

Jon
Man you left out mazdas own 4 rotor, lemans winning supercar motor.
The (dare I say) R26B
http://www.mymazdarotary.com/mazda_r...paper_html.htm
The (dare I say) R26B
http://www.mymazdarotary.com/mazda_r...paper_html.htm
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Originally posted by rotaryrevial
wouldnt all the advantages of the rotary be trown out the window with too many rotars because of the weight issuse
wouldnt all the advantages of the rotary be trown out the window with too many rotars because of the weight issuse
Its how much weight you have to move with each horsepower. A 200 hp 2000lb car will perform (almost) like a 300hp 3000lb car. There are some handling issues with the heavier car, but as far as drag racing, dyno-bating, and bench racing are concerned those cars are equal.
Roughly, each rotor housing will make the same power. There is some overhead for the intermediate housings and the hardware to support the beastly 3+ rotor engines, but relative to the engine power and weight remain the same.
That's the gist of it, there are a lot more vagaries to take into account, but that's the basics.
Would you turn down a 3 rotor making more power than a 2 rotor because it weighed more?
Its a balance issue, if I recall correctly. All the motors get out of balance and knock them selves over, getting gas all over the place.
However, three rotors do NOT blow up as evidenced by the 13G and 20B. And there are several sucessful manufacturers of four rotors that can be mounted in an RX series car. Before I decided that my GSL made a nice daily driver I was going to strip it, put a four rotor in, and have a race car.
However, three rotors do NOT blow up as evidenced by the 13G and 20B. And there are several sucessful manufacturers of four rotors that can be mounted in an RX series car. Before I decided that my GSL made a nice daily driver I was going to strip it, put a four rotor in, and have a race car.
Joined: May 2002
Posts: 5,972
Likes: 37
From: Ottawa, Soviet Canuckistan
Yeah those exploding 20bs.. (emphasis on the bs)And I would think that the power-to-weight ratio would get better. You start with 2 rotors which share an intermediate housing and have to carry the weight of an end housing. With each rotor housing you only have to add one intermediate, but no end housings!
So the more rotors you have, the less the weight of those end housings matter.
6 rotor? Wholy ****. Who built that, where, when and why the **** didn't they run it?
I want one. Or two. In a Jag built for a V12... or a Viper
Jon
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