i did some looking tonight for a shift kit for my car, i came across this in summit. then called granatelli and taked to a tech about it. it plugs inline with our connector on our trans, and is fully adjustable. it controls line pressure and torque converter pressures. and defintly firms up the shift. according to the tech, you can adjust your shift firmness to your liking, from mild to neck snapping. all for 130 bux from summit, mine will be here monday alnog with the rest of my parts.
here is the link to find out more about it. they also have one for the 4T65E too