A 235 or a 261 would be a better choice for an upgrade. Both are virtually bolt-in swaps, depending on the year of manufacture of the larger engine. A 1954 or early-production 1955 235 or 261 would be the simplest to install. Late 55-62 engines need a little more tinkering, but they fit the existing bellhousing and motor mounts for the 216.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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