So my WIZ 14 casts Scorching Ray at 5th level to Overchannel it. Because I'm not rolling for damage does my Scorching Ray still get the benefit of Empowered Evocation?
There's nothing about either of those that prevents the other, as long as you're casting an Evocation spell of 5th level or lower that does damage.
If it's a spell that does damage, but not an Evocation spell, then only the Overchannel will apply.
Also note that Overchannel does not require you to cast Scorching Ray at 5th level; it Overchannels any Wizard spell of 5th level or lower that does damage.