renahec

Hi,
hope someone can help me.
i have a 1994 prelude si that seems to have a really horrible shake or wobble coming from the front end and through the steering wheel at speeds over 55mph (left to right, not up and down) sometimes it's worse than other times and sometimes it's so bad that it makes the whole car shudder!
i have replaced the tires with brand new bfg's and brand new ar rims. i just recently had the front end re-balanced but it is still the same.
when we bought the car the rear brakes and rotors were totally wasted and i replaced the calipers, rotors and pads on the rear.
i imagine it could be possible that the front rotors have been warpped from being over worked. the fronts are being replaced this week though.
does anyone have any ideas? any help would be greatly appreciated.
thanks ..............Hec