[scottj]

The design of the stroked 427W is not suited to high-perf. Long strokes, with their high piston speeds make inefficient use of cylinder head potential. Small bores shroud valves and limit valve size, again limiting cylinder filling potential.

The 427w IS suited for low RPM torque, street-performance, and the available heads are well suited for that.

If you want a High-perf 427 small block you should be looking at a race block with the 4.125 bore. There are a number of small block heads available for those that flow upwards of 400cfm and make well over 800 hp on a 430 small block with a single 4150 Holley.
Scott