The Rhombus Rotary Engine: Can a Quirky New Design Top the Famous Wankel? Rotary engines have always been synonymous with spinning triangles. But what if they weren't?

The four-rotor was eventually replaced by a small block to become the Aerovette. When John Z. Delorean left to create his own car, he envisioned it propelled by a rotary engine as well.

Despite the rotary’s flaws, one American startup tried to argue the Wankel’s case—not in cars, but by bringing it to the waves in 11.6-liter, diesel-burning big-block form.

Having updated the car with a fierce 630hp twin-turbo 350ci small-block spinning a pair of Nelson Racing Engines 61mm mirror-image turbos at 9 psi of boost, the layout would need to flow just the ...