What mods do you have? What gears do you currently have? 3.08? Is your motor all stock except for the 70mm throttle body? 65mm would better suit your setup. Although I don't think that is why you are bogging. Do you have nitrous on your car? I imagine you don't...because you sure as hell wouldn't be bogging if you were squeezing!
This is a power adder forum. A moderator should move this post to the Windsor Power forum and you'll get more replies than you would here. Not as many people on this forum.
But...to attempt to answer your question. Are you injectors new? Or are they the same injectors that came out of the motor before the rebuild? If they are old...they could be clogged. What about your fuel filter? When is the last time you changed that? That could also make your car slower and your motor bog. Have you done all of the other tune up stuff? Plugs, cap & rotor, air filter and maybe even plug wires if they look worn or are pretty old. Give us some more info. on your set up though...it could help to better pinpoint the problem.