Anti-roll bar combination

[judgie]

you normaly want a bigger anti roll bar on the front. that way you keep the balance of the car the same. if you want a car that snap over steers and is harder to control then go bigger on the rear bar, not recomended.
you dont say what car your running as i wouldn't run a rear on a swing axle car.
for road use i wouldn't go above a 19mm front and a 14mm rear on a 1302/3
for a swing axle car a 19mm front and a modefied z bar would be my prefered set up.