Is my block sleeved? Take a look...

I'm sure there's a way to tell....I just don't know it.

It looks sleeved to me. If memory serves correctly sleeving is done when there are problems with a block. Such as cracked cylinder walls etc, or when the block is aluminum. If you want displacement measure everything and see what it is. 4(boreXstroke)

blocks are generally sleeved after something ugly happens. Or if the motor is being rebuilt, and needs a bore job, but its been bored out already and you need more material to work with.

As far as it being stroked, the crank will probobly be stamped with some kind of marking. Get an inside Mic and a depth gauge.
Put a piston at BDC
Bore diameter x Depth at BDC x 4 = displacement. Measure to the flatest part of the piston. Not on a dome or valve releive or anything of that nature.

There should be fairly obvious marks on the cylinder wall where the piston travel stops. Measure between the marks. Multiply that by the bore near the top of the clyinder wall.

There are multiple reasons for sleeving, most have been mentioned. One reason is if the block is being bored beyond the safe limit. It will add strength. If the block was stroked and bored for maximum displacement then there is a good chance those are sleeves. I have only seen drop-in sleeves so I'm not sure if that is a sleeve.

I do know that there are a couple different ways of securing sleeves. From what I hear if the motor was done right, then the sleeve will have a "lip" around the top. There will be a groove machined into the top of the block. The sleeve will slide down into the cylinder until the lip seats in the groove. The head will then clamp the sleeve against the block to keep it from moving. They can also be friction fit but this is less reliable. I wouldnt trust a friction fit at high RPM's personally.