[NovaMan]

Well, a stock-length (6.135") rod gives a rod to stroke ratio of 1.53:1, which is not generally considered the best. But if you use a 6.385" rod, that brings the R/S ratio to 1.6:1, which many people consider a pretty good compromise. I think if you go any longer than 6.385", the pin is up in the rings with a standard deck block (9.8").