Overheating 360 new engine

Post #59. The problem with those small fans is that they are [a] small only pull air through some of the rad core & [c] the fan shroud blocks a significant portion of the core, which will inhibit air flow, particularly when the car is moving. The fact that it might cool ok on that car does not mean that the fan[ s ] are doing a good job; what it means is the totality of the engine tuning, engine build & cooling system are keeping the engine cool. Coolant is a two-part process: cooling air + coolant. At idle & lower speeds, using a bigger rad can cover up for a poor flowing fan & a big high flowing fan can cover up for a too small rad.

The OPs engine may have an internal engine problem, such as tight pistons, rust scale on the cyl bores, causing excessive heat. Whatever.
Short of stripping the engine, the fix is more air, more coolant, more efficient coolant circulation &/or all of the above.
I read years ago on a cooling website [ info has now gone ] that their large, 7 blade clutch fan,
pulled 6000 cfm. Elec fans are not even close.