which one works better, a shift kit or using a computer to boost up the pressure in the lines? can u get a shift kit and do programming?

 

Shift kit. Programming really doesn't boost shift firmness at WOT since you're at 100% line pressure at WOT anyway. Programming doesn't take care of many of the issues that a shift kit does either (to do with the timing and speed of several different things.)

Regardless of if you have a shift kit or not, I would recommend leaving the tranny line pressure alone or at least not raising it much.

TCI makes a great shift kit that is easier to install than a Transgo but is just as effective.