I've got an S4 (bonestock) GTU with an Apexi N1 catback, and I was wondering, what size/brand headers and high-flow cat would go best with the cat-back? I was thinking racing beat for the headers and bonez for the high flow cat. Just not sure of what size would be good. I know that anything bigger than 2.5" is too much for an n/a. Any sound clips or video with a similar set-up would be appreciated. Also how much horse power would this entire setup give me?

 

SDJ or ISC racing header.

 

Size?

 

I got the rb header/ bonez cat combo from rx7.com on my s5. its a good setup.

 

factory header, bonez race pipe, apexi N1 catback no silencer. Sounds great.

 

That: Sizes on the piping? And any video?

Rotary Weapon: Video?

 

I think both are 2.5", they both make more power than an RB.

You wont see anything larger than 2.5" probably because it's terrible for airflow.

Also, the stock manifold, flows like crap.

 

Ok, I did a small search on SDJ and it looked like they were discontinued. If you could link me to a place that sells them that's be great. Suggestion on a manifold would be nice too...

 

This was the same setup I was running on my S5.
Yes, it is a nice setup but not exactly quiet.
I ended up swapping out my free-flow cat with a borla straight through muffler.
I am running 3" exhaust piping, it pulls hard throughout the rpm range!

 

http://www.rotaryinnovation.com/headers.htm

 

thanks.

 

if your not gonna run a true dual like the rb stuff i would go with the cork sport and rb pre silencer (such a good sound).

http://corksport.com/store/large/1ch..._A_Header.html

 

Any video or sound clips?

 

I think the corksport website has links to some youtube videos of their product

http://corksport.com/

 

pacesetter and a 2.5" magnaflow cat. then put the cash you saved towards a RB T2 catback.