Posted for "George Braly" <gwbraly@gami.com>:

  There is no 8.5:1 TSIO 550 engine in the published TCDS information
 available on the FAA web site.
 
 I can make the CHTs hotter on an 7.5:1 engine than an 8.5:1 engine at
 the same horsepower - - and vice versa.
 
 This is accomplished by one simple adjustment.
 
 Regards,  George
 
[ it should be noted that Darryl Greenameyer runs less
than 7:1 and alot of boost -Rob ]