360 HP Confusion. History of this motor?

My '78 Van had a stage 3 2bbl. 360 truck engine, regular leaded gas, stage 4 was a 4-barrel. Stage 1 was an unleaded 2-barrel, stage 2 was an unleaded 4-barrel.
So, my stage 3 had a 6 qt oil pan if I remember, and the heads had rotators on the exhaust valves. Don't know if this can help.