[3BarBoost]

Wow, gone for a week and has this conversation gotten clearer or muddier?

Only thing I want to add at this time is something about knock sensors. Knock sensors work by "listening" to vibrations in the block caused by abnormal combustion. This is a fairly complicated and imprecise process wherein the controller does some fancy DSP to figure out the level of knock and how much spark to remove - usually erring on the safe side. As spark is removed, boost and fuelling has to be adjusted to keep everything in the exhaust right at the correct temperature. Knock is classified as "abnormal" operation and therefore is outside of the calibration window where everything is tightly controlled - read that as less efficient. You can run a GT Turbo with 87 pump octane, but it will make less power and torque than a SVT, with poorer fuel economy - because it wasn't calibrated to run on that fuel.

A SVT is a lower cost vehicle to purchase and to own, and it will happily run all day long on cheaper fuel - getting excellent economy all the time. We expect to sell twice as many SVTs as GTs, because it scoots for not much more money than the base engine.