Ignore the sugar and only take the total carbs into account. Everyone is different so it would be a complete guess as to how much you BG will rise. If it was my daughter then she would need 1 unit of insulin to cover 13 grams of carbs and 1 unit would bring her BG level down about 6, so if she started at 13.0 then 1 unit would bring her down to 7.0ish.
The only way to be sure is to test yourself and record everything in a notebook, like snacks, times and what your BG levels are before and after at 1 to 2 hour intervals.
Hope that makes sense.