There is a Detroit 40 series that has a 7.6L (466 cu in) model. I didn't know it came in 330 hp - that is usually the bigger 8.7L model) - or that CC used it, but I guess that's it. Sorry, I don't know anything about the track record of that engine.
The "spout under the motor" sounds like an oil breather pipe, sometimes called a slobber tube because it drips oil. Noticeable blue/gray smoke there suggests that gasses are blowing by the piston rings and into the crankcase. However, white "smoke" is moisture and may merely indicate a lot of water condensation in the crankcase. If it's white, my first thought would be to change oil & filter and see if the problem persists. Another thought is to have an oil analysis done (take the sample before changing the oil) to check for the type of contaminants in the oil. That will give good clues about what it is and where it comes from. Blackstone labs can do an oil analysis, and some truck oil change shops (e.g. Speedco) can do it for you.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL