Engine Combo's that turned out terrible?

There's list of engine combo on here for 12 11 10 second ET's etc..

Just wondering if people can post combos they have done that just didn't work on the street and or track for one reason or another, or it worked really good at the track but a dud on the street etc... to give people an idea what doesn't work. And maybe what you did to improve it.

Or even combos that you/others thought would be terrible and worked out better than you/others thought.