so here's the information for guys who wish to put loud exhaust on their cars but couldn't do it for their car being a "family car"
solution
in the original piping of exhaust get i Y splitter of this kind...before catalytic converter or mostly known as "CHOTI DHOLKI"..
then the pipe till the rear bumper of the car
and at the end put a valve of this kind(of-course of appropriate size)
just open the valve when ever you want to make noise...when family is around keep it closed....
i think its the most simplest and most cheapest solution for this problem...
NOTE: you will need to keep an "OVEN GLOVE" in your car always...valve will be extremely HOT...
if the sound get TOOO loud then add a nice muffler at the end..