I thought that GM got out of the class A chassis business, and stopped making their large 8.1L V8 several years ago.
So they only have a 6L engine to put up against the 300+ HP V10?
I don't think I would want a GM van based class C.
As for a Ecoboost V10 - I don't think that will ever happen. What they can do with a 3.5L V6 is impressive! Double the displacement, and you would get what? 600+ HP? You really have no need for that many horsepower in any RV.
I have hard rumors of a new head design on the 5L V8 that might lend itself to direct fuel injection - sooo?? ? ? You might see a 5 liter or 5.4L V8 ecoboost, but probably nothing larger than a 6.2 Ecoboost. Even the 6.2L is really to large for turbocharging, the crank can only handle about 500 HP before you start to shear off the crank mounting bolts. . . .
Lets see what comes out next year.
Fred.