You are never going to find any engine block that is ideal because of core shift, only what you are willing to live with for your intended purpose. The major thrust side cylinder wall thickness is the most important thing to look at, not the front to rear core shift which has very little thrust force applied to it compared to the side to side loads as the crankshaft rotates. And this side to side core shift of the cylinder walls is the most critical and important. Only a sonic checker will detect and confirm these thicknesses and core shift for you. The Mexican block castings are typically thicker than the USA or Canadian blocks, but I have also sonic checked a few of them that were no thicker. So never rely on what you've read as fact and only rely on actual measured data from yourself or your machine shop.
