Is that a end cylinder or not?
I have had a bunch of stock blocks sleeved for different reasons, I ended up learning that you can sleeve a block like yours two ways, pressed in with a press in interference fit from .0025 to .0040 or chilling the sleeve in dry ice and heating the block up enough to allow the cold sleeve drop in or be push in by hand with a .00010 to .0010 interference fit. The pressed in with the tighter fit can and may affect the cylinder wall shape on the cylinders beside it which may need a lot of honing to make them round again . I now plan on installing all four sleeves on the side needing the sleeve unless I'm going to have it bored and honed to the next over size and buy new pistons
Either way make sure and use a good sleeve sealer on the sleeves that go in all the cylinder that have cracks in them

Thanks Cab. I have decided that it makes sense to go to a new block. I have always wanted to go aluminum and i am using this as my excuse. I assume there is some value in the megablock since it can be sleeved.
I talked to Todd at Marsh performance and have my name on a World aluminum block that is on its way to Todd.

Sonic the cylinder. My bet its thin. It split, let water in that cylinder and coughed the gasket due to rough deck surface. Could have been worse. Hydro locked and taken out the rod and block.
Doug

Again, there is no corrosion in the bores. This motor has never been shut down for the day until it was run for several seconds on gasoline and still very warm, like above 180. It had dyno pulls on it and eight passes total after being honed and reringed. What may look like corosion is a depression you can feel, it is that deep. The cylinderwall colapsed.

as to the tight dowel register fit, i think that would have been caught during assembly ?

I dont think lube makes much of a difference Jim.

They are more like stains that look worse than they actually are.

I found that just shutting the alky off and running on the primer isn't enough. Seems like fuel will still be left in the barrel valve, lines and nozzles and drain and drip into the engine. After I have run mine for a few minutes I blip the throttle several times before I shut it off.