Hey guys and ladies,

I've been doing a lot of searching and not getting a lot of answers... Looking to add HFCs to my Motordyne TDX-II catback. I would LOVE to do test pipes, however I autocross in STU which requires cats within 6" of the stock location.

The goal of this modification is to free up what seems to be the most restrictive part of our exhaust, while staying STU/street legal, and not sacrificing sound. Initially I was looking at Berk HFC and Kinetix (even Z1Motorsport), however have found many people stating they are loud and there is a hiss to them.

My latest research has pushed me towards resonated HFCs. And that brings me to two options:
ARK resonated HFC
Fast Intentions resonated HFC

In your opinions, is resonated the way to go (worth the money)? Who has some experience with these products? Any videos? How about mating them to my TDX-II?

Thank you in advance for your help, and if there are any threads that I've possibly missed in my browsing please point me towards them!

Manny

 

In my opinion stay away from anything resonated so close to the engine. I personally feel no resonator can handle the heat in that area leading to broken packing and creating rattles and blockage. I would do a berk hfc if i were going to remove the oem cats.

 

Thanks for the input! Are you currently running Berk? Any thoughts on Z1 HFCs?

 

find the ones with the highest flow, most places put their cell count on their websites. if i remember correctly the lower number means higher flowing because the cells are bigger. someone correct me if i am wrong

 

I did some quick searching and found this link...
http://speed.academy/how-catalytic-converters-work/

About 2/3s down it explains cell count vs flow, seems flow is directly correlated to cell count and length.

I'll start checking around for flow rates through the aftermarket cats though, good thinking!

 

hey mVP I am in the exact boat you are. Did you ever find a HFC you liked? Any droning? Rasp?