Hey guys, I am STUMPED, I have a 98 Cobra. . . I put an air fuel guage in a while back and was under the car trying to run it from teh o2s and then i realized after trying EVERY wire from both o2s that i could just do it under the hood, so it was all taped up or whatever . . . anyway, guage is working great. . . .it always backfired when it was cold, but then when it warmed up it was fine, well, i'm having major problems now, if you floor it, anything above about 5,000 RPMS it missfires HORRIBLE, it just backfires and jerks, and it's incredibly slow. . . anyway I figure, well original plugs and wires, thats my problem, so i replaced them with MSD wires and stock plugs from Ramchargers. . . anyway, it idles smoother, but still backfires horribly. . . . ANY IDEAS?  My only thoughts was maybe with all this snow, i have to floor it up my driveway and i can hear the snow hitting under the car, and I thought maybe it got in one fo the wries i spliced under there cuz maybe i didnt tape it up good or wahtever, but no check engine light comes on so any ideas guys? anyone else have this problem?

Thanks, Jon