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In a pure race scenario like NASCAR (no comments on NASCAR's purity, please) the engine builders tend to go bigger bore and shorter stroke. So much so that there is a maximum mandated bore spacing on new engines. Bore spacing tends to limit piston size. So a bore spacing limit is a de facto piston size limit.
The closer your engine application is to a pure race engine the more you'll want to find that bigger bore, assuming displacement is limited.

I remember back in the day I spent a semester reading all the old SAE journals in our engineering library. It was awesome! Articles by Fred Duesenburg on the advantages of double overhead cam engines with power curves, articles by many of the big guns in American engine development. At the time I was interested in Ford flatheads. The trick as I saw it was to get that elusive Mercury crank and offset the rod journals to get the biggest flathead one could drive on the street. Then I read an article from the '50s which had dyno curves for the same block and compression ratio but with 3.75, 4.0 and 4.125" cranks. Remember that on a flathead most of the breathing is controlled by the ports in the block. I was flabbergasted to find the three horsepower curves maxed out at the same power, nearly exactly. The lesson for the flathead was that power stays the same, displacement only determines what rpm it occurs at.

Now for a modern street engine that all goes out the window. As ports get bigger and bigger and flow more and more the limitation of an engine's power tends to become the displacement of the engine. This was apparent back in the 426 Hemi days where one had to rev the snot out of the 426 to get big power. It should have been a 488 right from the start, then it could have been really something as a street engine. But now with 350-400 cfm heads all over the place it seems one has to build the shortblock as big as possible just to use the heads available. And the increased power from using the heads' flow potential is greater than any added inefficiencies from R/S ratio. There are also the mountain motors that are making unreal hp/cubic inch with R/S ratios of 1.38 or so. There are also the Enginemasters winning combos which tend to be short rod engines.

The last part of this lecture is about the myth of stroke vs. torque. Like so many things in the mechanical world, It doesn't happen exactly like one would think. Given a piston/cylinder combination with a certain displacement, the longer stroke would "seem" to produce more torque. But for the same displacement, the longer stroke makes necessary a smaller diameter piston. Smaller diameter means smaller area for the pressure to work on. Conversely, a larger diameter with more area has less leverage because of the shorter stroke. I think it evens out. We need to look back at our lives and remember all the times we heard something like "long stroke means high torque" which was actually written by the advertising boys. It wouldn't be the first time that the general population believed a falsehood because of advertising.
In point of fact because smaller bores generally inhibit head flow the longer stroke production engines were usually designed to have maximum cylinder filling (meaning peak torque) at lower rpm. Larger bore engines promote head flow and could be cammed to have maximum cylinder filling at a faster engine speed producing more horsepower to boot. On the street the "high torque long stroke" engine would have most of its maximum torque available from off-idle to the torque peak. It'd set you back in the seat. A short stroke engine would have its torque peak at a much higher rpm even though it may be the SAME number, but because most street driving occurs at a much lower rpm the shorter stroke engine operates most of the time far away from its peak torque. So it seems to prove the short stroke low torque idea even when the two engines produce the same peak torque.

So I don't believe your question has merit on the street. The real answer is build the biggest shortblock you can afford. Then you put heads on it and increase flow when you get more $$$$. One more benefit of having a big engine under moderate flowing heads is you don't have to spend gigabucks on a high rpm valvetrain or rear gears. Thanks for listening.

R.

There is a lot of evidence that suggests a shorter R/S ratio is advantageous when using a port with large cross-section. Can anyone take this statement a little further