Mazda’s “Holy Grail” engine is one of the most advanced engines we’ve seen in recent years. With fancy spark-controlled compression ignition and a mild-hybrid setup, it’s supposed to return near-unbeatable fuel mileage. But its arrival to the United States market might be delayed.

A new report from reveals Mazda is still trying to figure out how and when to bring the engine here, despite stating it’d be available “in some American markets in late 2019, to follow everywhere in 2020.”

One consideration, the outlet identified, is cost. The Skyactiv-X engine is high- tech, brand-new and that costs money Mazda is perhaps unsure it will make back in our market.

The other, frankly, is power. Currently, the Skyactiv-X is a 2.0-liter engine that’s found in Mazda3s in Japan and Europe and the CX-30 in Japan. It and there is some concern that isn’t enough for U.S. buyers. Mazda’s executive officer for powertrain development, Eiji Nakai, told Automotive News the automaker is testing out computer simulations of the Skyactiv-X technology with larger displacement engines.

Furthermore, Mazda engineer Yoshiaki Yamane seems to believe bigger engines with more power are more in line with our driving habits. “Maybe U.S. customers require more power, because fuel economy is not the top requirement,” he said.

There is some logic to this. People who prioritize fuel economy will probably beeline toward the , not a Mazda. And last year, 50,741 Mazda3s, compared to 154,545 CX-5s.

If Mazda’s going to stick the Skyactiv-X anywhere, it’s probably going in the CX-5, because buyers have at least shown their preference for those over anything else Mazda currently makes. There’s a business case for it there.

Anyway, we’ve reached out to Mazda for confirmation of this possible delay and will update if we hear back.

A Mazda spokesperson responded:

“We haven’t announced our plans to introduce the Skyactiv-X powertrain in the U.S. Mazda is weighing a number of factors for our market, many of them mentioned in this article. When the powertrain launched last year the European market was prioritized after close study of regulatory requirements.”

“During the Los Angeles Auto Show, we learned already 60 percent of Mazda3 sales in Europe were Skyactiv-X. That being said, higher horsepower engines are more common in North America, where we currently offer the Skyactiv-G 2.5 in the Mazda3, among other models, and Skyactiv-G 2.5T in the Mazda6, CX-9 and CX-5; each of these are more powerful than the Skyactiv-X 2.0 engine in the Mazda3 in other markets.”