Yes actually I've owned 2 civics and a GTI.
When you have a VTEC engine, once you get to a certain RPM (like
5,500?), the VTEC kicks in. It, I don't know, messes with the cam or
valves or something, and maximizes torque. When driving, you can feel
a little change in power once it kicks in.
When you have a turbo engine, once you get to a certain RPM (mine
starts spooling at like 2k lulz), it, I don't know, does something with
air pressure or whatever, and gives you more boost. When driving, you
can feel a large change in power once it kicks in.
I think it wasn't too much of a stretch to make a comparison.
I don't know anything about rotary engines but I just was told by an
old Mazda tech that the purpose of a rotary engine is sort of vaugely
the same as VTEC's purpose.