[FenwickHockey65]

There's some credibility to the rumor, Achates's design is a 2.7L and that NA engine production forecast a few months ago predicted a 2.7L, Achates was targeting a late 2018 launch for the engine coinciding with SORP for the T1XX trucks (and I believe they said they already had a manufacturer application for it), and it's certainly a ground-breaking engine which GM would want to make a big deal about. If it was just another turbocharged 4 cylinder, I don't see why they would do a press reveal yesterday and embargo any information until tomorrow.

I guess we'll find out tomorrow. Someone on another site who claims to be involved with powertrain development also confirmed there would be a 2.7L engine, but we know how that can go.