[olddog]

Obviously either engine can be built and made to run. Usually each approach requires robbing Peater to pay Paul or visa versa. So it's a matter of choosing your poison. I suggest understanding the costs, and drawbacks with each.

For example, one point to consider. On the block you plan to use for a 4.125 bore, how thin will the cylinder walls be? Will there be adaquate room to bore further on the next rebuild? However this may not be important to you.

On the longer stroke option, what needs to be done to the block for clearances? How close are the wrist pins to the rings? Are you forced to thin rings and do they seal up well? What has to be done to get it ballanced up.