If only the Mazda 6 had more time, we could have seen the next model coming in with the new engine. The new engine which was showed off when Mazda took the covers off the new Mazda CX-9.
According to Mazda, the new engine was designed to be compact so that it will have no problem fitting into the other Mazda models. Since Mazda will be upgrading the Mazda 6, their fans have been hoping that the upcoming model might come in with an upgraded engine but that might not happen.
While Mazda has not made any official announcement yet, it is highly unlikely that Mazda would come with the new engine. It might fit perfectly but adding in a new engine will mean that they will need more time to upgrade and modify the vehicle and time is not what Mazda and their Mazda 6 has right now.
The new Mazda CX-9 came in with a 2.5 liter turbocharged four-cylinder engine that will be offering about 227hp and 310lb ft of torque.