Actually as important as the amount of sugar, the graivty of the beer and the temp of storage has a bigger bearing on thing..
at how many weeks are you tasting/openning your beer and declaring it under carbed/tasting funny?
How long and at what temp are you storing them to carb? If it's under three weeks
minimum and below 70 degrees (for NORMAL grav beers), when you are testing them, then there is nothing wrong but impatience...Storage temp, and gravity are the two most important important factors in carbing and conditioning...
Stouts and porters have taken me between 6 and 8 weeks to carb up..I have a 1.090 Belgian strong that took
three months to carb up.
ANd even if they are carbed the flavor might still be off...that's called
bottle conditioning.
ALL beers will reach their level of carbonation eventually. In fact, it's possible (and proven by running the numbers in beersmith) to NOT add priming sugar and get
minimal carbonation of a few volumes in time (in old brewing british brewing books they didn't add sugar to some ordinary bitters, and milds and relied on time and temp to do the work naturally. in fact if you run the recipes from the books in beersmith many of them give you NEGATIVE sugar amount to reach the lowest volume of co2 for the style range-and that NO SUGAR would often get you either mid carbing range or the highest volume of co2 depending ont he recipe.)
More info can be found here....
Revvy's Blog, Of Patience and Bottle Conditioning. There's even a video.
If you added the amount of sugar that came with your kit, then that is the correct amount of sugar....most beers carb at around 2-2.5 volumes of co2, and for most beers that is 4.5-5 ounces of sugar...that is plenty.
Just make sure they are at 70 degrees and don't worry about taste or carbonation until it has been AT LEAST 3 weeks at 70....I never even concern myself til 8 weeks......
