mguner
How many is too many?
The cylinder bores are not staggered from bank to bank. Notice the split rod and common bearing shown in other pics from the link below. This was used in the XP-72 a modified version of the P-47 thunderbolt. Notice it made that power at 3400 RPM.
http://www.enginehistory.org/Museums/chrysler.htm
http://www.enginehistory.org/Museums/chrysler.htm