sandgito

I bought the blitz but i didnt get a catback system..

i currently have a 99 gs300, i had it for about a year already and i think its time for me to do some upgrades on it. i installed a short ram, sway bars for front and rear. after installing that my car still feels a little loose around corners. some people told me to try and upgrade my under car sway? but i cant find any.... :( secondly, purchased a blitz exhaust. i want to know if anyone can recommend me a good cat back?