CBattaglia,
An Accusump is a very simple accumulator. It is a piston inside a tube about 4" diameter. One end of the tube is solidly closed and can be pressurized with air.
The small air pocket provides force on the piston to move the
oil into the engine block. On a 460 there's an entrance to the oiling system just above and behind the mechanical fuel pump location, toward the front of the cam chain cover on the driver's side. Others have suggested using the gauge port at the top rear of the block but I have not tried this location.
The Accusump is pressurized by the
oil pump when the engine is running, and if the engine
oil pressure drops, the Accusump's pressurized air pocket forces oil into the engine's oil passage.
The capacity of the Accusump is one, two or three quarts - I use the three quart size on my 460s.
There's a valve located between the Accusump and the engine that needs to be opened after the engine starts (or just before starting the engine if pre-oiling is desired) and needs to be closed before the engine stops to prevent all the oil from being moved from the Accusump into the engine.
The valve can be a simple ball valve, or an electric pressure switch and solenoid valve combo depending on your preference. I have used both methods (on different engines).
There's a pretty nice explanation of this at
http://www.accusump.com/accusump_tech.html
Hope this helps,
Tom