I did a little research on sleeving all four holes. The 153 blocks are plenty thick and have free standing cylinders. This prevents cylinder to cylinder distortion and promotes proper cooling.

The recommendation is to use ductile iron or centrifugal cast sleeves, which is all my machinist uses for both strength and wear purposes. It?s a race shop.

Thanks for double checking behind me on this. I?m sure that I can?t think of everything and several experienced heads are better than one!

Never use a minor caliber bullet on a major caliber adversary