Two old adages that come to mind regardless of what kind of engine you're working with- - - - -

"There's no replacement for displacement"- - - - -

and

"Horsepower is to brag about- - - - -Torque wins races!"

With the right piston/rod/bearing combination, it's possible to get 3/8" more stroke from a 235/261 crankshaft. That can be massaged into a gain of around 40 cubic inches, whether the starting point is a 216, 235, or 261 engine. It requires some serious metal butchery, but it's doable- - - -without altering the outward appearance of any of those engines. A 258 cubic inch "216" with close to 9:1 compression can turn some heads at the top of a long hill, leading a pack of other "stock appearing" stovebolt trucks!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!