There's a very interesting post on PPRuNe about problems with the Centaurus specifically due to the supplies of the required oil specified by Bristol back in the day no longer being available. Apparently the sleeve valve engines are very sensitive to the grade of oil used and despite using the closest spec to the requirement and running well below combat power settings and lowering the TBO it clearlyo ain't working.
Doesn't come as a huge surprise to me given they took 10 years just to make sleeve valves work at all.
(At this point if you're interested in WW2 piston engines I highly recommend The Secret Horsepower Race
which a brilliant history of British, American and German engine development)
I work for the company, but hey, don't let that fool you. I'm really an OK guy...