Danny Popp's car runs a 388ci (4.125" bore/3.622" stroke) setup that revs to 9000rpm.... I wouldn't exactly call that stock
He also runs a crazy light Tilton 5.5" triple disc clutch/flywheel combo for super fast revving engine. It works for him that is for sure.
My buddy Rich Wilhoff runs the yellow C6 Z06 with a built 427ci from Katech (4.125"bore/4" stroke) keeping revs under 7K RPM and was also in the Optima challenge and won the series overall.... just not the winner takes all event in Las Vegas. His car makes around 575rwhp and 80rwtq more than Danny's. Rich said he doesn't want to give up the torque...
I would say more cubes and therefore torque is preferable unless you have big $'s to make a high revving short stroke setup.
If you are serious about AutoX or road racing you want an aluminum block. An engineer would give his left nut to shave 80lbs off of the front end of a car.