318 stroker

Hi everyone I am new here and I love MOPAR. I own a 1965 dodge dart gt 318. I have a new 318 bare block bored 30 over and would like to build a 390 stroker motor. I have a set of stock recondition rods, a new set of Kb pistons flat top 2 valve relief around 9 to 1 cp. I have been told just replace the crank with a 4.00 crankshaft to convert the engine to a stroker is this true? If not what parts will I need without buying a kit.