Is it difficult to understand what you put, Anillary will be to change segments I suppose, what is the busy to change?
I suppose that what was done to the engine would be segments, valve seats, shackling of cylinder head, check the cylinder head and rectify the seat plane over the block.
The hot connecting stinging failure may be due to two causes:
1st that gasoline is bad or has less than 91 octans rum. And self -led.
2º That the rectifier has passed by removing material and has excessively increased the compression ratio, so that hot connecting rod when you accelerate thoroughly.
If it is because of this last reason, you can do little, you will have to raise a cylinder head, put a thicker butt joint and possibly colder spark plugs.
All the best.