You mentioned rod stroke ratio so you understand the concept. I like the longest rod I can stuff in the engine, will not see a performance increase, but the longevity is what I am after. My last engine is a 4.25 stroke 4.5 bore with a 7 inch chevy rod, it makes tons of torque, and just over 800HP and revs to 7000 like a smallblock. very happy with the combination.