Lost my first engine ever this weekend after having buit my own for almost 20 years. Just curious what you guys think may have happened. It is a 740+hp 406 SBC 18° heads. I am turning it to about 7900. First off here is what I know. #6 rod is in multiple pieces broke about 1" below the wrist pin pin/small end still move ok no evidence of heat there. The #6 journal is black and severly trashed like something was welded to it and then forcfully removed. #5 is dark as well and the bearing was beat up. All the other rod bearings look ok except for some having evidence of trash going throug them. The cam wont turn (probably bent) and it sheared the teeth off the timing belt (Jesel) It bent a couple pushrods and broke one in two. It appears all the exhaust valves have made contact with the pistons. although they still appear to be sitting flat against the seats I havent pulled the last couple rods or the crank yet I am still pretty sick its going to be a while before I have the cash to replace all this stuff. I just want to see what I can find out about it to prevent it if possible in the future. I usually put about 300 passes per season on my car and it usually gets freshened every winter. We had a baby last year so I only put about 140 passes on it and decided not to pull it down last winter. It was on its 271st pass when it let go. The rods had 1 prior season on them and we upgraded to L19 bolts and had them resized last time it was apart. No warning other than it didnt rpm like it usually does. The oil pressure was good when I staged. Because the journal is black I am thinking an oiling problem or something happend to the rod to get it mishapen. The thing that puzzles me is why #6? its pretty much in the middle of the crank. Odd thing is I did crack a stock block in the bore years ago using this same crank and it was #6 cyl as well. The crank has been maged and checked for roundness each time it was apart with no issues. A buddy of mines dad works for a company that builds polishing equipment for the big 3 and some of the larger crank companies. He took the crank into work and had it polished to within 40millionths of being perfectly round with a 1ra surface finish. So I know the crank was right. The rods were eagle H beams. I will post pictures when I can get them uploaded to a host.