WATCH: Biggest Rotary Engine In The World Has 12 Rotors

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That's the same number of rotors as six Mazda RX-8 engines, yet is the size of a Chevy big block V8.

We're big fans of unorthodox engine designs, and the insane 12-rotor rotary engine that Rob Dahm has just featured on YouTube is nothing if not unique. It's the only engine of its kind in the world, and no major automaker has ever been brave enough to build one.

The man behind this engine is Tyson Garvin from Apex Manufacturing and Design, and he took Dahm - a fan of rotary engines who often races his four-rotor Mazda RX-7 - through the thinking behind creating the 12-rotor mill. Remember that Mazda's rotary engines in both the stock RX-7 and the later RX-8 only had two rotors.

But what makes a rotary engine so special in the first place? There are a few aspects, but one of the primary features of it is that instead of reciprocating pistons that create a rotating motion in a conventional engine, rotary engines have a triangular-shaped rotor that spins on an axis. They also have no valves which contributes to far fewer moving parts.

Rob Dahm/YouTube
Rob Dahm/YouTube
Rob Dahm/YouTube

Garvin explained that in building engines for speed boats, he and his team had done pretty much all they could with a Chevy big block power plant, whereas the scope for a rotary design was larger.

"We started measuring a big block Chevy and seeing how many rotors [we could] fit in that spot," said Garvin. "In the end, we came up with this design that is the exact shape of a big block Chevy. I basically made it to replace my boat engine."

When put on a dyno, this 12-rotor rotary engine made around 800 lb-ft of torque at just 2,000 rpm - from a naturally-aspirated engine. And that's just a taste of what the engine can do, as it'll be able to spin all the way to 10,000 rpm.

Rob Dahm/YouTube
Rob Dahm/YouTube
Rob Dahm/YouTube

Dahm then points out that this monster engine is essentially comprised of three rows of four rotors. One of these banks of rotors spins backwards, a decision that was made to create the aesthetically pleasing and symmetrical placement of the exhausts.

The team then proceeds to disassemble the 12-rotor engine, with the ultimate goal of building on Garvin's creation to realize this work of art's full potential. This process will be documented on Dahm's channel in the days and weeks ahead, where each and every component (and there are many of those) will be meticulously checked as the team gets closer to firing up this beast.

The possibility of turbocharging would probably give this engine the power to rival electric hypercars (that four-rotor RX-7 already makes upwards of 1,000 horses), and likely with a truly special soundtrack to go with it.

Rob Dahm/YouTube

This ambitious rotary project is completely at the opposite end of the spectrum to what Mazda is doing with its Wankel engine these days. For production purposes, the reliability issues and high appetite for oil has seen the Japanese marque mostly abandon its famous rotary; one can only imagine all the oil that would be needed to keep Garvin's engine running smoothly.

Then again, Mazda does currently make a single-rotor range extender engine for the MX-30 that will be sold in Europe, and the USA could see the tech at some point in the future as well. A true rotary-powered sports car to serve as a spiritual successor to the RX-8 and RX-7 is still something Mazda wants to develop, but such a car is likely still some time away.

2008-2011 Mazda RX-8 Front Angle View Mazda
2008-2011 Mazda RX-8 Engine Mazda

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