I think it has more to do with RPMS Than HP. A single line can support up to 7000 RMPs anything over that need a double line(one on each side of the pumps stator). The swinging pick up is installed to accommodate the style of pan that you are using ie: large rear sump or dragster style). I've used a center sump with a static single line for 8 year now. I have about 650-700 hp and shift at 6700 RPMs.