With distinct camera angles, mood lighting and a bewitching soundtrack, this video of a 4-rotor rotary engine going together is the right way to produce an engine-assembly video. Not only is the production top-notch, but the engine is also unique and compelling.
At just over five minutes and set to the enthralling music of Ivan Torrent, this video shows the team at Defined Autoworks in Graveport, Ohio, building a 4-rotor engine for a Mazda RX7 road racer that used to compete in the NASA Super Touring class.
“We had the shop for about seven years, and the car’s been around for five,” explains Logan Carswell, who runs the shop along with Matt Ripley. “Since we were building the engine totally from scratch and wanted to make it different than any other 4-rotor, we decided to document it.”
Even though their recording equipment was limited to a GoPro and cellphone, Defined assembled a wide array of enticing footage with different lighting, fast- and slow-motion segments and parts closeups. It’s all backed by Torrent’s instrumental titled “Human Legacy.”
One noticeable missing element is a dyno test at the end, although we do hear the engine idling in the car.
“Just haven’t gotten that far yet,” says Carswell, noting that additional work on the exhaust and fuel systems are required before the engine is broken in and then dyno tuned. “We’re looking for 600 horsepower to the wheels. The ultimate goal is to get 750.”
Unique for this engine is a custom 5-main-bearing setup that required a special 4-piece eccentric shaft. The engine also features three spark plugs per rotor, variable-length intake trumpets, slide valves on the throttle bodies and aluminum side housings.
“The extra center bearing helps reduce flex at higher rpm,” says Carswell. “Every other 4-rotor I’ve built is in the 9,000 to 10,000 rpm range. Ours has the capacity to go 12,000 rpm.”
The extensive use of aluminum helped bring the engine’s overall weight down to just seven pounds more than a traditional 3-rotor engine. The triple spark-plug arrangement requires an additional Electromotive controller — one handles eight coils and the second works four coils. Electromotive also handles the fuel delivery to four Injector Dynamics 2,200cc injectors.
“The port work inside the motor, the overlap, the intake and exhaust tuning — all that is pretty specialized,” adds Carswell. “The main goal with this engine is to prove that it’s reliable and eventually we can hit 800 horsepower at the wheels. That means about 1,000 horsepower with a naturally aspirated rotary engine.”