72 Demon slanty-to-340 Resto

What is the stroke on a 340 vs 318 crank. I know all small block rods are the same length. arent they both a 3.31 rod ratio? If so the only advantage the 340 has over the 318 is bigger bore size and a forged crank
Not sure about rod ratio, but I'm guessing they have the same stroke. This replacement crank on jegs suggests so Mopar Performance P5007253: Forged Crankshaft 318/340 "LA" & 5.2L Magnum Main Journal Size | JEGS