exhaust question

[Ookami330ci]

I plan on buying a catback exhaust for my s13 in a few days. The exhaust i found says it has a 3" inlet.

Was wondering if 3" inlet would be a direct bolt on to a stock catalytic converter?

Ive searched yahoo and this site and cant find any info on this.

[fliprayzin240sx]

Doesnt matter what size the piping is, as long as it uses the same 2 bolt patterned flange, you are good to go. Just be aware, if you're slapping this on an NA car, it will probably be loud.