Honestly im not sure, my engine was making a rattle sound only when the rpm's dropped (around 2,000) for just a sec. Rev'ed and drove smooth, thought it might be a converter bolt. Checked them and one was a little loose. Tightned it, didnt hear the rattle, so I went for a test drive. Gave it some gas, boost kicked in, heard a loud bang, knock gauge went red, then engine seized. I was close enough to home that I drifted into the garage. Dropped the pan saw a ton of metal, bottom of the piston is broke off and half of the crank is up the other half down, snapped right in half. On a side note, I do not have powerlogger, but I have scanmaster 2.1 and a knock gauge. I have never had any knock to speak of until this. I have however had a issue with the engine shutting down at full throttle (loud pop, but nothing on the knock gauge, or scanmaster) but as soon as I let up a little it starts pulling like crazy again. When I was under the car checking on the converter bolts I noticed a "white and red rebuilt" tag on the drivers side of the engine. I would put stock back in it, but since I dont have the skills/knowledge to do it all myself, and am lucky enough to have scottatk and a few local guys willing to help me with the swap, I would rather err on the side of caution and overbuild. I will just have to buy 1 peice at a time, and hope for a lot of overtime at work, lol