That's because the technology behind the fuelinjection or the combustion process remains unchanged.
Direct injection requires low-sulfur fuel because of issues having to do with the high pressures encountered in common-rail direct injection technology (this holds for diesel as well, and is one of the reasons the US doesn't get modern DDI engines (and GDI as well).
And since Valvetronic only affects throttling, the common conditions requiring high-octane fuel (typically high compression) are untouched.
That's to say a Valvetronic engine combined with DI and high compression will likely require low sulfur, high-octane fuel just like an equivalent conventionally throttled engine.
Direct injection requires low-sulfur fuel because of issues having to do with the high pressures encountered in common-rail direct injection technology (this holds for diesel as well, and is one of the reasons the US doesn't get modern DDI engines (and GDI as well).
And since Valvetronic only affects throttling, the common conditions requiring high-octane fuel (typically high compression) are untouched.
That's to say a Valvetronic engine combined with DI and high compression will likely require low sulfur, high-octane fuel just like an equivalent conventionally throttled engine.
