Custom Hi Flow Cat

[Norm]

I wanted to just ask. According to australian standards a cat is always necessary for on road use. But are there different types of custom hi flow cats? I'm jus curious because i'm buying a used toda headers with a custom hi flow cat welded on to it that isn't modified by toda, but are there different qualities of custom hi flow cats? and what is the lifespan of one of this steel ones?

Norman

[lowie]

main difference is the 'cell per inch' part of the design.

Stock is probably something like 400-500 cell, which as you can figure out means there's lots of little holes in the inside of the cat, which affects flow.

I believe TODA and other performance catalysts are 100 cell and is the best for airflow

ie 200 cell


compared to a 400 cell




you can see how the 100 cell is less restrictive.
Also the 400 cell stock-type ones get dirty and the little holes get blocked making it worse

I would recommend the xforce 100 cell catalyst, which is stainless steel and either 2.5" or 3".
I got mine fitted from westside mufflers, they did the same to Yona's car from JDM yard and the difference between power figures on his civic was 1hp atw on and off.
ie. it flows really well...
There's also the length and width of the cat and all that, shorter=better, and width should just match the rest of your exhaust system

not sure how a 100 cell cat would do in a emissions test but.


edit: er the first picture was actually a 200cell cat, but you can still see the difference lol. a 100 cell cat would have bigger holes