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BTW if they really have made this work and it shows up there suddenly is an avenue for modding that hasn't existed (really) on the current Skyactiv platform.
See, Skyactiv has a high compression ratio, which is how they get their efficiency. But this means they have to be very "active" in management to avoid detonation, including VVT, ignition timing and similar. That in turn means adding a scroll to get more power is problematic as you quickly run into the limits of pump fuel.
CI engines have no such limit because detonation is not a consideration. As such as long as you can deliver the fuel you can shove more air in there and the penalty for coming up short on the fuel is that you don't make more power -- CI engines by definition run lean all the time except at full output, and that's perfectly ok!
The limit on being able to add more boost and fuel is strength and heat-dissipation related; if you go too far you lift the head (the pressure exceeds what the head gasket and/or bolts can hold), you melt something or something in the driveline (usually the bottom end) fails mechanically and catastrophically. That's wildly different than the world you live under the rules of in the SI world where you are forced into higher and higher octane fuel in order to prevent detonation, and ultimately the area under the curve that results in safe combustion makes further boost ill-advised (unless you want to run straight methanol for fuel or some silliness like that!)
It is entirely possible to get 50% output increases out of most CI engines from "factory" configurations while running straight-up and CHEAP pump fuel with "reasonable" safety, and with some strengthening (e.g. girdles on the bottom end, high-strength studs for the head, etc) a fair number of people have gone quite a bit further without winding up with internal engine parts on the outside of the block. I know a couple of people who have doubled the output of the ALH TDI engines (bigger turbo, crazy-increased flow injectors, higher-range MAP sensor plus the tune to use all that) but you wind up changing a LOT of other parts in the driveline (final drive, clutch, etc) because utterly nothing was originally designed for that and some (the clutch, specifically) will be destroyed immediately if you don't.
This could quite-easily be in our future if those crazy Japanese Mazda dudes have actually made HCCI work.