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Stroking and then Turbo/Supercharging an inline-4 is kind of counter-productive.
Stroking an engine is an easy and relatively inexpensive way to increase the torque of an engine across it's entire power-band. That said, it makes for a generally slower-revving and (and sometimes lower-RPM) engine because the pistons/rods have to travel a longer distance on each stroke. This can be countered however by using lightweight rods and pistons to keep rotating mass low. An example would be using The hypereutectic pistons, which contain more silicon in with the aluminum, to create a lightweight, low-friction piston. While they are lighter they arent as strong as, say heavy duty forged pistons used in boosted applications, so adding boost to this combination is not a good idea.
When boosting an engine, it is a good idea to de-stroke it, to allow for a quicker-revving, quicker-boosting and higher-RPM engine. Instead of relying on a long stroke for torque, you rely on the forced induction to increase the torque, and a shorter stroke for higher RPMs and thus higher horsepower. The de-stroked crank is a good thing when you're adding heavy duty parts like billet steel rods and forged-aluminum pistons to handle the increased cylinder pressures, because it allows the engine to rev (and thus get into the boost range of the turbocharger) quicker than the longer-stroke engine.
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