Wanna get a flowmaster for my 2002 maxima SE but i dont know how to go about choosing a size or how the sizes work, any suggestions.

 

It's a maxima bruh.... not a 72 split bumper camaro with an LS6 ....

I'll suggest you look up several videos with different set ups, to get an idea of what you want...there is one thread of a guy that did all custom exhaust but by what i read i didn't sound so good