Hi,
its not so much as 'enough' but rather 'more is bette'.
The 'crack' that you are talking about sounds to me like you don't have enough output inductance.
You may recall in one of my first posts in this thread I indicated that you need some inductance in the output between the capacitors
and the weld arc. If you don't, or have to little, the capacitors discharge in a short circuit manner and tend to stick the rod to the job and produce a crack.
With enough inductance you will get a 'constant current' which is the appropriate mode for stick welding.
The capacitors are to make the most DC voltage from your transformer/rectifier combination but the its the output inductance turns that into constant
current required for MMA welding.
Craig