Lookie what I got!

Cool! What was it orginially designed to power? Mazda clown-car?

~ Chance

Remote control airplane. I don't have one yet, but when I get one, this will be the powerplant.

Is that for a rotary go-cart? That would be badazz!!

That ought to spool like crazy.

Ladies and gentlemen, you're witnessing a very rare species of sea urchin that are only found in the remote sea bed off the islands of Kunichimobobo.

Is that a Wankel Rotary Engine capable of powering the flux capacitor to get to the remote sea bed off the islands of Kunichimobobo?

That is so f'n cute!!!! <3

Weed eater? ☺

The new HDS Wankle??? I musta missed Hogo's GB on this one.

Now I wanna build a mini carbon arc with one!!! Anyone, off hand, have power specs?

coolness i love the wankal wasnt there a 1.3 liiter version that had 300 hp
?

The Wankel turbo flashlight-put 2 individual Lithium ions in and it runs for over a year....

Hello? Mazda clown car? Boy, tuff crowd! Hard to get a laugh. What this thread needs is a three drink minimum.

~ Chance

Considering how much a Wankel sucks back, three might not be enough.

raggie33 said:

coolness i love the wankal wasnt there a 1.3 liiter version that had 300 hp
?

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Wankel engines are often rated incorrectly. Mazda's standard Wankel engine is rated at 1.3 liters, but Mazda only rates the displacement of one side of each rotor -- not all three sides. Mazda can get away with that because the math for rating Wankel engines is really wonky. Functionally it's a 6-cylinder engine, but you get two combustion cycles per crankshaft revolution like a 4-cylinder piston engine. And while the Mazda 13b engine is capable of revving to 9000rpm, it produces the power equivalent of a piston engine revving to 6000rpm, because it takes a Wankel engine 3 crankshaft rotations for all of its combustion chambers to go through a complete combustion cycle, whereas a piston engine only needs 2 crankshaft rotations to accomplish the same.

Going by displacement alone, the Mazda 13b is not a 1.3 liter engine, it's a 3.9 liter engine -- the reason why it's physically so small is because 3 combustion chambers can use the same hardware, whereas a piston engine requires separate hardware for each combustion chamber.

This wonkiness is the reason why Wankel engines were banned from Le Mans after Mazda won in 1991 -- it's just too hard to figure out exactly how big of a Wankel engine a team should be allowed to run, in order to be fair competition for other teams running piston engines.

Using my eyeball-caliper, I think this little model-airplane Wankel engine is also rated according to a single side of the rotor. It's rated at 4.9cc, which looks like a reasonable estimate for the maximum volume of one combustion chamber. What that means is, it's actually a 14.7cc engine, which is ENORMOUS displacement for a nitromethane/methanol powered engine of this class. However, the 4.9cc rating may actually be an appropriate comparative rating in this case, because normal RC engines are 2-stroke piston engines, which require only 1 crankshaft rotation to complete a combustion cycle -- the same as this engine. However, this engine is a 4-stroke, meaning that it separates the intake and exhaust cycles from each other, minimizing the amount of fuel wasted out the exhaust -- but at the same time, it constantly has one combustion chamber actively combusting while the other two are preparing for combustion or venting exhaust, so like a 2-stroke piston engine it doesn't waste any of its momentum preparing for combustion or venting exhaust. In fact, it's even better than a 2-stroke piston engine in that regard, because even a 2-stroke piston engine is running on its own stored momentum for half of each crankshaft rotation.

It's just a shame that Wankel engines are so hard to seal properly, and have such poor volumetric efficiency, or they would be indisputably the best form of positive-displacement combustion engine ever invented.

WarRaven said:

Considering how much a Wankel sucks back, three might not be enough.

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My RX-8 doesn't get fantastic gas mileage, but it gets much better gas mileage when I drive it like a sane human being. The biggest problem with Wankel engines is people look at the 9000rpm redline (or in the case of this little guy, 17000rpm) and they treat it like a goal instead of a limit. Yes, you do need to rev-up a Wankel engine to get it into its power band, but you don't have to redline it every time you rev it up. I'm quite happy driving my RX-8 between 3000rpm and 7500rpm under normal circumstances -- 7500rpm to 9000rpm is a nice little reserve for those tight situations.

Good grief that's huge.
To think my little single is around 2-2.5 hp at the crank, this could be up there a bit. The power to scale is immense.
I can make these bead lock tires in my avy into pizza cutters on one cylinder.
That Wankel must be for a mighty big bird.
Thanks for sharing.

Had a 87 and 79 RX7 at my leisure as well as a 70 Alfa Gtv, two 70 German Capris when I was in my late teens.
The rotaries needed red lining on highway every week to keep torque up, or they sucked fuel period.
Raced the Alfa, on and off street. Capris too, they ate the RX7 badly. 58mph first gear.. I'm O/t sorry, 1.2 an 1.3 👍
Carbed was cooler. Multi carbed Capri, ruled, 3x2.

That had an old school offenhauser manifold, dual plane, equal bore, had a plate made so I could swap noisy weber carbs out for throaty Holley double pumper, 600 I think it was, may have been a 650cfm, huge on that six cylinder.
Although I got smoked by a hot rod Mx3 71 I think, imported, multi carbed, dual point dusk distributor set up with juice. Buggers ☺