Mine had 236000 on it when I got it, it had never even had the head off. It did need a rebuild, though. Burnt valve on #5, and several of the rings were broken. I think if the maintainance is kept up, they'll go as long or longer than any modern "throw away" engine in todays cars.
BTW-It is the 216, not the 261 that has the babbit bearings, though I do beleive that the early low pressure 235 had the babbits also.
