I'd use actual, not corrected. Not just for all of the many good reasons above, but it seems like Wallace calculations are given with the assumption that the chassis/traction/gearing is totally optimized. I've always used the conservative number, so there's a high level of confidence you'll run close to that projection. If the car is totally sorted out sharp, and you have awesome DA, then it'll be a nice surprise when it runs faster than the projected number.