It is a well known fact that reciprocating engines generally last longer, run better and are more cost effective if, operated regularly. Lycoming gives those who operate on manufacturer's TBO hours/calendar a little gift:
="Paragraph Eleven http://www.lycoming.com/Portals/0/techp ... hedule.pdf
11. If an engine is being used in “frequent” type service and accumulates 40 hours or more per month, and has been so operated consistently since being placed in service, add 200 hours to TBO time. (Engines identified in AD-2012-19-01 are not eligible for this TBO extension.)
Full SI: http://www.lycoming.com/Portals/0/techpublications/serviceinstructions/SI1009AY%20TBO%20Schedule.pdf
Note #1: Most folks flying Part 91 have their TBO times based on field inspections (PART 43) and common mechanical sense. Check with your insurance company and/or stake holders however. I flew PART 91 for .gov and was not allowed over TBO during flight.

