You had previously stated that the engine was running well before the crash, so something obviously changed as a result of the crash. We recently maidened a new GP Extra 330 with an OS 55 AX and it was exhibiting exactly the behavior you are describing (idles well, ran well at full throttle, but transition was poor, and it would deadstick at mid range). This engine had a Pitts muffler. After doing some more research, I found out that the OS 55 AX is very sensitive to low exhaust pressure on the tank. We had to plug one of the outlets of the Pitts muffler to raise the exhaust pressure, and that cleared up the problem. Now the engine runs beautifully.

In your situation, its possible that the crash resulted in damage to either the exhaust pressure nipple, the exhaust pressure line, or there is a small leak in the fuel tank itself that is releasing pressure. Before you mess with the tuning, make sure that all your exhaust pressure connections are not leaking.

Brad