Hey guys i need help on my exhaust, i jus bought a 2.5 inch Tanabe medallion exhaust. and it didnt come with a cat, anyways i wanna put it by myself but my cat on my car is welded to my exhaust right now. so im planning to buy a new cat

so my question is that do i have to buy a cat with the same radius as my exhaust which is 2.5 inch? and i have a ls/vtec on my car right now. do i have to buy a cat that is compatible with my engine? so the sensor i have in my car will fit with my cat?

please and thank you ihave no knowledge on this so any help would be great please and thank you

if yo dont understand what im askin please jus write down what u think or what u know please and thank you.

 

If you dont need to pass smog, just throw in a test pipe or have one made. Any muffler shop can make you one.

 

well id rather have a cat

 

theres aftermarket cats from magnaflow that cost around 80 bucks.. flanges can be bought at the muffler shop.

and yes, if you have 2.5" piping, you want to keep that size thru the whole exhaust system. if theres a bend or crush that narrows your 2.5 to any less, you now have 2,5" pipe that functions to whatever the size of the crush. So make sure you stay with mandrel bent piping in the future.



A comparison of a crush bent 90° angle (top) and a mandrel bent (bottom).
Notice how the crush bent is significant’y smaller through the bend.

 

does it come with the sensor? or i can use my o2 sensor right now?

 

use your sensor.

 

okay thank you.

 

If you want performance get a performance cat, a good brand you will use your factory o2. Honestly the exhaust will give you minimal performance without a CAI and headers.

 

Even WITH an intake and a header you will get minimal performance gains.

 

randomtechnology.com makes bolt in 50 state legal cat with flanges. i changed from a dx exhaust to and ex moving the cat to under the car i bought a random technology bot in cat and ive never had a problem with it for 3-4 years now