When should the Converter Lock Up?
 

When I did my swap to my LT1 I kept my original 1990 700-R4. I used a painless wiring kit and it needs to be hooked to the brake switch for the TCC lockup to work. Now I can feel the converter locking in every gear, but not right away it only seems to lck in if you are crusing at an almost constant pace. Should it do this or should it only be locked in 4th? If it should only lock up in 4th what do I need to do to correct this problem?