Snakeplane

Did Airlines or Aircraft owners who purchased the Old prop liners Like the DC4 Tune the engines to get the same performance or close to the same performance of say a DC 6 or a constellaton or would it be possible to do that and is it smart to do it i know that due to the airframes stresses but would it be possible and safe to get a type rating on an aircraft because i want to give the Cal Classics DC4 the same power of a DC6