The 155 hp figure would account for a 12-hp drop from that of the outgoing MX-5, though, a corresponding weight loss should still improve the power-to-weight ratio for the 2016 model.
Now, the CAS page could simply be following previous reports, including one from Autoblog. As recently as October, it was being reported that the MX-5 would be powered by a 2.0-liter, Skyactiv four-cylinder, a version of which is producing 155 horsepower and 150 pound-feet of torque in the Mazda3.
Naturally, we've reached out to Mazda for comment – or perhaps even confirmation – on the info from CAS, although we aren't expecting a reply until at least later this morning (darn time zones).
Mazda wasn't willing to confirm or deny the figures cited by the Chicago Auto Show, although we're betting the 155-horsepower figure is a bit on the low side. As for the CAS page, a Mazda spokesman told Autoblog that they "aren't sure where they got that number." The horsepower estimate has since been pulled down.