Years ago I attempted to ferment Mountain Dew (about a decade ago so my recount of the details may be a bit off). My goal was to have a drink with similar carbonation, similar flavor, and reasonable amount of alcohol. Talking with some coworkers who were amateur wine makers, they suggested using a champaign yeast. I took a 5 gallon carboy, filled it most of the way up with Dew, added yeast, and added granulated sugar until it was sugary enough for that particular yeast to thrive. I don't recall how much sugar was added but I was shocked that the Dew itself didn't register high enough by itself when tested.
When the fermentation was complete, something to make carbonation was added, it was bottled, and put in a cool dark place for a month or so. When I finally tried it, the results were a bit disappointing. There was a flat, yeasty, slightly bitter & alcohol taste, but the Dew flavor was almost nonexistent. All in all it was a fun experiment that I couldn't wait to try again.
My questions is this... I got a Mr. Beer kit as a gift and I thought about trying my "Dew Brew" again. Is there anything I can do to get better results (more of a Mountain Dew flavor with better carbonization)? Do I need different equipment? If the problem was that the Dew was already fairly diluted (relative to most pre-fermented liquids) would it work to go get a bag of the syrup that is used in soda fountains?