How about these figures Paul ran into this the other day doing a google search
485 Ft. lbs. Torque at 2800 R.P.M.
315 H.P. at 4000 R.P.M.
90° V-10 O.H.V.
488 Cu. Ins. (8L) 4.00" Bore x 3.88 Stroke
Compression ratio 8.4:1
Weight 1100 lbs fully dressed
this is a marine motor being made in Canada right near Algonac, MI
check it out their boat test for a repower was done with a 37' Chris Craft Constellation.
http://www.kent.net/amp/index.html