Posted for "George Braly" <gwbraly@gami.com>:
 
 Scott,
 
 That  output for the motorcycle is really not very "exciting" compared
 to an aircraft engine.    Correct it out for  RPM and  the Hp/cubic inch
 is around .51.
 
  If you take away the liquid cooling,  and run the heads at 380dF
 rather than 240dF,  the octane requirement would increase substantially.
 
 George

"""
 Hmmmmm.... My Honda VTX motorcycle, 110 ci (55 ci/cyl) comes close to my
 320 (80 ci/cyl).  It uses a 9:1 compression ratio, 4" bore x 4.4"
 stroke, 3 valves, 3d mapped fuel injection (MAP, OAT, RPM, etc.) thru
 12-hole electronic injectors, 2 plugs/cyl, EI, liquid cooled (uh, well
 that's quite different), etc.  This engine produces 95 HP and 115 ft/lb
 at the rear wheel thru a less than efficient a drive shaft at about
 4500-5000 rpm. It requires 86 octane auto gas.
"""