Sup guys

I'm going to be getting a used RB headers system and HKS catback exhaust off an S5 that I will be putting on an S4. I'm planning on installing a gutted cat too.

I was planning on installing the RB headers and having a muffler shop make the extension to hook up the cat to the stock y-pipe.

Now, do you guys think that the stock y-pipe is a huge restriction? Would it be worth my while to track down an aftermarket y-pipe?

Am i forgetting anything in my plan? Fitment issues?

Thanks y'all
-Grant

 

i just put RB headers on and a hiflo cat. I bought a set of mufflers form a local muffler shop and had them welded on. Im not too sure if the stock y pipe is a big restriction...but i noticed substantial gain when i put everything on.

 

kick ***! Thanks for your anecdote...anybody else?? Fitment issues?


-grant

 

No issues whatsoever.

If you get it, the RB presilencer is exactly the right size for the gap between the headers and the Y, so no welding needed.

 

I have to run the gutted cat/normal cat so i don't get fined 3K dollars.

Wow...so no fitment issues, thats good.

 

oh yea for fitment issues... go to [url]www.mazdatrix.com ...they sell cats that bolt directly up to the header...see if you can call them and get the measurement of the extension they weld onto the cat...I bought a miller hiflo cat and took it to my local welder and had him weld an extension onto it wen i ahd my mufflers welded on

 

O thanks for that tip. That will come in handy.

wait...i just thought of something...if this HKS is supposed to be a "cat-back"...how come the y-pipe isn't part of that assembly??

-grant

 

you got no y pipe with it?

how much did you pay?

 

um i have the hks dual hipower catback..it comes with the y-pipe

 

really?? this is all used stuff...100 for the RB, 250 for the "cat-back"...

maybe it slipped my mind, ill go look at the pics again. Perhaps it does have a y-pipe..i hope it does.

So how does your HKS sound?

 

ohhh 250 for the "catback"...haha not bad...my mufflers were 65 a piece and i ahd them welded on for $100

my header was new an it was 187 bucks.....sounds really good...id post a sound clip if i had one

if you really want to i think mazda trix sellls an aftermarket y pipe...but im not sure if it any bigger

 

"I Hate Ricers", so do I.

 

o..thanks for that all so relevant response.

i'm with you all the way though. I think all those asians are compensating for something with those huge exhaust's.