"Larry Dighera" wrote in message
...
On Wed, 03 Jan 2007 15:39:56 GMT, "Steve Foley"
wrote in g7Qmh.5$Jf.4@trndny03:

I wonder what it would take to produce new performance graphs for
modified aircraft? It would seem the FAA would require them to
certify the modification.

They are not required for engine upgrades. That has certainly affected the
performance of my plane. I increased the HP from 150 to 160 and put on a
cruise prop (58" to 62"). I get similar takeoff performance as before, but
cruise much faster (relatively - it's still a fat-wing Cherokee)