So I'm going to be picking up a ~335 volt pack tomorrow that holds about 2kwh of juice. If I break the pack down to ~170 volt, what will this do to the kwh capacity?
It won't change the kilowatt hour rating of the pack much since that's a measure of total (Volts x Amp Hours).
A 340v 40ah pack has the same KWH rating as a 170v 80ah pack.