37fen: 8 iron
The 8 irons are notorious for seldom doing what you think they'll do, or what they should do. I do everything I can to avoid ANY 8 iron shot. Some kind of glitch. I had those same irons and was spooked any time I had to use the 8 iron. Most inconsistent iron in all top sets (not sure about below 90 level).
But, it pales in comparison to the erratic, take-a-guess, hope-and-pray-when-you-hit-it Big Bertha 3wd. The circle of precision for the BB covers any area in the mini-map, boundary to boundary, even on dings, and especially on Par 3 tee shots.