Hi there,i have a 2003 wrx ,it has a stainless exhauhst ,the back box has been replaced ,there is a straight through pipe with no boxes of any kind up to where the exhaust goes up to the turbo....but the pipe going to the turbo has a box/filter in it but this is not the standard exhaust up pipe...its now coming up to mot time and im a little worried i have no cat....can any tell what they think i have on my car and if there is a cat in the up pipe?any help please....

 

pics would help. sounds like it may have a sports cat.