I asked this same question of the gurus at the RJS retail store near my house. They told me that 2-3 weeks with chips in the carboy during bulk aging should be enough due to the increased surface area of the chips. They told me to taste after 14 days, and if not oaky enough, leave for another week and taste again.
They warned me that you can always add oak, but never take oak out. If it tasted oaky enough after 2-3 weeks, they said re-rack and then age to let the oak integrate and mellow with the finished product.Edited by: Dean