Even if they did a carryover engine they would still need to test it. You see mules running around for mere cosmetic refreshes of certain vehicles. They test everything and even more so if the actual platform, suspension, etc have been reworked. That's why im so surprised there has been absolutely nothing on the Si yet.
See my post above. Manufacturers can test certain upgraded models in plain sight if they really wanted to (depending on what the differences are). I think when we see spy photos of small cosmetic changes/updates it's done on purpose by companies to generate buzz and talk about an upcoming update/refresh. It's silly to camouflage and public test small nips and tucks when they have wind tunnels to do it in.
