You haven't disagreed with anything I have said but you have made up scenarios to disagree with. I was speaking of a 1954 mechanical fan, no clutch on those. Don't know if the SBC year he has, has a clutch. You can mount a non clutch on it.
No use in discussing scenarios of what a "motor pushing more power" needs. That is off topic and encourages off topic discussion.
A clutch is much less likely to fail than an electrical fan's thermostat, motor, wiring, fuse, connectors and plastics.
The in-radiator transmission cooler feature does not affect the temperature of the coolant in the radiator. Adds no impact.
1. Did he tell you how much power he is making? If not, you have no more idea than the rest of us and helping make an informed decision is helpful. The greatest majority of SBCs also have clutch driven fans, so the failure rate of those clutches is relevant to the discussion.
2. Say what you will, I have had more mechanical clutches fail than electric fans. To each their own on what they trust.
3. Basic thermodynamics: trans fluid is run through the radiator to cool it. More heated liquid == more thermal load in the radiator. More thermal load requires more airflow to keep it cool.
As the OP has solved his problem, locking this down.
