408 Scat Stroker Kits

Is this referring to a cast crank as well as the forged? Wouldn't 6500 RPM with a 4 inch stroke be a pretty high piston speed for cast?
55,000 plus street miles 700 plus runs at 6400 rpm. Used to drive it to the track race it and drive it home. CT to Cecil county. Cast crank. Still running it, but with 12.2 to 1 compression now.