Quicksilver is right. End of the day, the 3800 was built by someone on an assembly line. GM follows strict guidlines regarding torque specs & oiclearences. Thee 3800 is a very reliable engine because of this. And it shouldn't be a surprise that they are not reliable when these details are overlooked. Also, the variation of rod weight can be extremely wide. I found out that 1 of my l32 rods weighed 14.9 grams more than another (from the same engine). 14 grams of unbalanced weight at 6000 rpm is at least 600 pounds of crank flexing force from that 1 rod alone. This explains why some 3800's are fine being revved to 7k rpm, and some break at 6300. It is important to balance any 3800 that will be used with a big cam at high rpm. GM obviously didn't pay close attention to the balance, probably because they used pretty beefy parts in thier supercharged applications and they were intended to handle boost, but not necessarily high rpm's.

Tricky little bastards I tell you.