Should i upgrade my car or just save up for a new one? specs in detail?

My car is a 96 infiniti i30 with a v6 twin cam 24 valve. I got it from my uncle, he takes very good care of his cars and it has 130,000 miles on it. So, first of all, i'm new to this whole car thing; is my car fast? is it worth upgrading? if it is, how much would it cost to upgrade? All my friends drive something fast, like a evo 9 or a 2011 camero, they all drive their cars to those legal racing circuits and race each other. I would very much like to join them.