Bore, Stroke and rod lenghts...
346: 3.898 x 3.622
348: 3.910 x 3.622?
382: 3.898 x 4.000"
398: ???
402: 4.000 x 4.000
414: 4.060 x 4.000, 4.000 x 4.125?
421: 4.030 x 4.125
427: 4.125 x 4.000, 4.000 x 4.250
434: 4.030 x 4.250
Ofcourse there are many other combinations but these are the common LSx ones.

