Actually, i take that back....stock z6 or y8 sleeves can take a lot more than 220whp. I was thinking about stock pistons and rods! Wow im retarded. Sorry about that bro. I have a friend in Cali who is on 400+ hp on stock sleeves and hasnt cracked one yet. Although that is definitely pushing it, but he is a professional builder.

As to your question, sleeves range anywhere from $800-1000 depending on what kind + labor. I wouldnt advise going with a blockguard as it causes overheating problems, plus you have to go to a shop to get them to sit it flush on your block. Running925 feels differently and im sure will post up...however me and many others feel this way.