I just guess I'm confused. In the examples given from the GM shop manual the 283 and the 292 share the same bore, but the 292 has a 1 1/8" longer stroke. Yet when you look at the torque versus displacement the 3" stroke 283 out torques the 4 1/8" 292. Granted, it's at a higher RPM, and not by much, but it still produces more peak torque when diplacement is taken into the equation. So using the numbers provided by GM, a .060" over 283, which is a 292 would have slight, and I mean a slight torque advantage over the original 292. So in this example, what did the 1 1/8" stroke gain us?
As Panic states, it is a very complex subject and the variables are many. My opinion is, when displacement remains equal, an increase in stroke does not increase torque. I do agree the easiest way to increase an engines torque output is to increase it's displacement, and the easiest way to do this is install a longer stroke crank.
John
