different harmonics . . . different crankshafts . . . different rods/pistons . . . ???
Then, how can the 235 and 261 harmonic balancers (41-55 3701930 and 53-55 3704338 and 55-57 3729417 and etc) for the same years work for 235 and 261 truck engines?
Go ahead and do what many of us have been doing for many years - use whatever harmonic balancer works with your combination of pulleys. If I was interested in worrying about something, I'd worry about the different diameters affecting cooling (but I don't, because it does not seem to do so).
