Smoke Simulation Scaling, Direction, and Blockyness Problem

Hello, im a student attempting to make a short clip of the galactica slugging it out w a basestar but i cant get the smoke simulations for the turrets to scale correctly, as well as the projectiles to emit their own smoke. I also cant figure out how to create a explosion without heat rise(flack like stuff). Sorry for all the problems, but i also cant figure out how to add smoke trails to the engines.images These are the types of explosions i am going for