Hello, This is my first post here so before the question I'll give a quick intro to myself. I'm a convert over from ORC since they are becoming a bit lacking in the tech area over there. For those that were there my user name was 73K20. I have a 1973 K20 that has been in my family since '74. Two years ago I did a frame off rebuild of the truck because it was in such horrible repair (PO's were father and grandfather /forums/images/graemlins/crazy.gif). Truck originally came with 350/350/205 and D44 front, 14 bolt rear. About two months ago I swapped out the TH350 for a SM465. Now that the tranny is in that i want (the TH350 was horrible) I'm in the machine work stages of rebuilding a 350 for it. I had a two bolt core at my house that i took to the machine shop last week to get the standard work done: hot tanked, baked, bored, decked, and alignment of mains checked. Yesterday I called the shop to check on the engine. Guy tells me that he hot tanked it, baked it, checked everything and was boring the next to last cylinder (number 3) when he discovered that this particular cylinder was bored crooked from the factory (the brief history of the core is that it came out of a '77 Monte Carlo my dad bought new and was never rebuilt). About half way down the bore he said that he heard the tool start to skip and by the time he reached the bottom the tool was only engaging approximately 1/2 the bore. The engine was being bored .030" over btw. So he overbored the cylinder and sleeved it (without consulting me first). Now the question: Whats the scoop on sleeved engines? The good and the bad? Seems to me that this should only be used as a last resort in a special engine or something where that particular block needs to be saved and reused, but not in an engine as common as a 350. I think that the main issue that is plagueing my mind are head gasket leaks. Another question is what is the deal with a misbored cylinder. Is this possible? Anyone out there hear of or experience this? For what its worth, I'm having him assemble the engine because he gives a 12 month/12,000 mile warrenty with his work. I have however got his word that the cylinder sleeve will never cause me problems and if it does he will repair/fix the engine free of charge. I have talked to MANY people that have had work done by this particular engine builder and no one had a bad thing to say about him. All were shining remarks. The point I am at right now is I'm willing to take his word and use the block, but I'm still unsure about it Sorry about the long first post but I'm going to have quite a bit of money tied up in this and just wanting to know previous experiences and suggestions on what to do. Thanks.