wat up bro's, this will be the third catalytic converter that i had purchased. Long story short i have a 99 si, i have a jdm **** racing mugen replica header (4-1), which goes to a cat back A'pexi n-1 style exhaust, i have purchased a Blox racing test pipe, and i hated it, not enough back pressure after 7,000rpms it fell on it's face it felt like. So then i came to the resolution to get a REAL high flow cat. Unfortunately i bought off of ebay a no name high flow cat. which im sure everybody here already knows that it is really just a resonated test pipe, so again im not pleased with how it drives, plus the check engine light is on and i have emissions/inspection soon. Now i have heard good things about the company Catco catalytic converters. Now my question is can i buy a DIRECT fit catalytic converter from them and have it bolt right to the A'pexi piping and the header? It seems like it would work but it does not give dimensions on the piping size, or the flange/bolt whole dimension.

 

man, no answer maybe i'll just go to NWP from now on.

 

Does your existing header/exhaust combo work with the OEM cat? If so, it will work with a direct fit Catco cat. If your header has a 2.5" collector for example, It won't correctly mate up with a direct fit cat and you'll have to have one custom fitted.