i havetwo questions my sway bar is 5/16" in the front. and i would like to know if i would upgrade it to 3/4", would i also need to doto the rear.

and why is the after market one for the rear bigger than the one for the front? whould it not be the other way round.

addco rear is 7/8"

 

for all you who would like to no i found this on http://www.roadraceengineering.com/3g.htm.

(Suspension Techniques Rear Sway Bar
The stock GT rear sway bar is 20mm diameter, the ST rear bar is 22mm diameter.
This rear sway will make your car handle better by making it more "neutral". Stock, the factory gives you a car that "understeers" some. When you have the car all leaned over at the limits of adhesion, the front tires have a little less grip. By installing a thicker rear sway bar (and leaving the front bar stock) you will make the car more neutral.
The down side, you need to be careful of what you wish for. If your car is nice and neutral, when you chop off the throttle suddenly the car can kick the tail out. The bar is an easy direct bolt on replacement for the GS and GT models.)
If you would like to read it all go to the web site.