We need to make sure that the next generation of advanced IC engines isn't just swallowed up and eliminated by whatever has killed off the Tucker car and other advances before we ever saw them. An earlier version of an OPOC engine was called Ecomotors; their website, ecomotors.com has disappeared and they may have simply been bought up and shipped to China, videos can still be found searching on ecomotors on Youtube. The Achate engine is a better design with crankshafts both below and above the pistons rather than the Ecomotors design with exo - connecting rods. Compression is between pairs of pistons rather than between piston tops and cylinder heads, the design being basically an advanced two-stroke with fuel being injected after the ports close on power strokes.