To Stroke, or not to Stroke

Here is my thought process.

If you have a 383 magnum, you have X HP and Y torque. If you up the CID and built it in a similar fashion, you should have a percentage better of both. Sort of the same concept of 383 magnum to 440 magnum. The 440 magnum is always going to make better HP/TQ than the 383 Magnum in stock trim, so why not when both are treated equal? If I had a 383 Magnum in my Duster, and dropped in a stock 440 magnum, wouldn't I benefit from the added HP/TQ, or would the added weight cancel it out? What would need to be done to the 440 to overcome the weight disadvantage?

My question is, does a big inch motor have to have a super aggressive cam to run? I knew a guy back in Texas that had a 67 Barracuda Formula S with a 536 CID motor that sounded like it had a little more than a stock big block. I'm sure he had more than $4K in his motor as it had Stage V Hemi heads and two radiators, but it was very streetable. Why can't my 512 be?

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