Sleeved block for race engine

[Ruairidh Dunford]

I have had a number of engines come in (some sleeved and some not) which exhibit the damage you describe Tony. All of them had very high lift cams and very strong valve springs which I considered the root cause of the failure.

The blocks had lifted on the valve side and snapped the base off around the (normally number four) bore. In the cases of the ones with sleeves, these had certainly not moved and remained in position as you suggest.

Good blocks are indeed hard to find.