I recently tried to bore a Hemi block to 2.913". It made a clean cut up to 2.871". It cut through the sleeve at 2.891". Some folks have said that they will take the 2.913", but I know of only one guy that it worked with. And that was an old non-hemi block. I sent mine off to have a sleeve put in for the 2.913". It's a smaller sleeve than the typical 3" bore sleeve that you get from NR or Isky. I bought it off of Summit Racing for $26 and its long enough to cut in half and make two sleeves. I have had several Honda blocks sleeved for 2.992-3.031" bores. The sleeves are around 3.180"-3.25" O.D. The larger sleeves will cut into to upper bolt holes so it's best to use one that is closer to 3.180" or you'll have issues with the top head bolt threads. There's no real issues inside the block when using the 3" bores. Actually there's less clearancing to do in some areas because of the bigger bore. I always recommend that any 3" motors have bracing welded on, but I have seen a Honda 3" motor make 27 hp on my dyno without welding and no issues. Also I had an unwelded predator make 28.88 and multiple pulls to 9600 rpm. I was standing back for sure, but it held together.