Hardblock?

[carl hinkson]

Originally Posted by Bill Bogues

On our 267 chevy we took a 305 block and sleeved it down to 3.50. Didn't fill it and had reasonably thick cylinder walls. Still leaks 2 to 4%after 60 runs. Aftermarket block is the best way to go but we ended up with a decent block for half the price of aftermarket.

From what I have seen with sleeving blocks and more so all eight sleeves put a lot of unwanted stress in the block and after a few heat cycle the cylinders don't stay round.