The answer to your question is a definite "maybe". As was mentioned above, an original-equipment V8 radiator in good shape should cool a stock 350 without much of a problem. If you add some "go-fast" goodies to it, you'll definitely need some more cooling capacity. The 600+ HP 350's we ran on the circle track needed a pretty hefty aluminum radiator, a good shroud, and a high-flow fan to keep 'em cool.
Jerry

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