ok i have a h22 thats got darton sleeves in cylinder four the sleeve began to sink in all cylinders the rings blew what is the largest the cylinders can be bored and can a cylinder that has begun to sink fixable i will post pics soon

 

Are they wet or dry sleeves?

I'm going to assume your block has the Darton dry sleeves. I would think it would be hard for wet sleeves to sink down if the block was machined properly. As far as I know the dry sleeves cannot be bored they have to be replaced. If they are slipping then the remaining FRM H sleeves are probably to large and out of spec for the dry sleeves. I would say that you are probably looking at having to get the block machined for a set of wet sleeves.