Dammit all to (well)
Thought I posted a reply earlier----must have hit close instead of submit :drunk: :drunk: :drunk:
I would think you have a plugged radiator or weak water pump.
don't need no stinking fans @ 70
I have a tall 4-row in my 79 454, The only time it even gets warm, is when I'm in traffic, not moving. (twin 12" electric since 1990)
Fans only come on after I shut the truck off (yea, I know, not wired to an ignition circuit--straight to battery----lot younger & Dumber then

)
I would imagine a 3-row would be fine for a sbc, Perhaps it is plugged???
Even the small radiators in these trucks were overkill for most applications.
Try to find a 454 rad----they are 4-row---If you already have the tall radiator (pretty much as tall as the core support) only mods will trimming the isulator mounts. If you have the shorter one (about 4"below the top of the support) you will need an upper mount and some nut-serts to mount the upper mount.
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