I'll be doing a 2.35lt build soon, which will be on my daily runner.
I'm considering running a full de-cat, however, I work some unsociable hours & have to keep the neighbours happy.

So i'm wondering if there is a decent de-cat system I can run, which will be not that loud on start-up with low revs, but have a decent tone/note when the loud pedal is pressed!!

Cheers
Iggy

 

I also work funny shifts and use my car daily, uk 99 year 2000 turbo. I have a s/steel magnex centre (de-cat) and rear box fitted, and its does not wake the street up but sounds ok on chat.
I have just added a s/steel japspeed de-cat down pipe, its still ok for noise but the system sounds lovely on chat, and the car runs a lot better. I did add a 255 fuel pump and mapped ecu too.

 

I've searched but can't locate an exhaust schematic for a MY07 RB320 (STi Type UK PPP).

just wondering exactly how many CATs & what sections I need..?

 

They dont make magnex exhausts anymore they went bust, scooby clinc did sell them. I am sure you have a cat in your up pipe too, might be wrong tho. I can only afford a lighter classic.

 

No cat in the uppipe on an STI..........

Will also has the later pattern downpipe/second cat arrangement???






Full Info page.........
http://opposedforces.com/parts/impre...llustration_1/

 

Cheers Don,

So all i'd need is, Open mouth de-cat down pipe (which is the only CAT), straight through centre section & back box?

 

Yup, and that will be F'kin loud
So your going 2.35 now ?? Nice

 

I don't want ridiculously loud Rog, except on full chat
Yep, 2.35lt but still only running 450 to 500 with matching torque, but well within it's safe limits of 600/700

 

Well a cat will make the exhaust note quieter than a de-cat. If you have neighbour issues now i think a de-cat may exacerbate that mate. Ah b0ll0cks too em .

I hope your going to do a thread in the OC on this build mate. We want a step by step

 

I didn't get any issues with the neighbours with MY05 Blob STi Type UK, which was loud!
But the one neighbour does't like the Blitz when i'm putting it in the garage..

There must be a De-Cat system that's not overly loud!!

 

Could possibly try Cobra Trackday Friendly True 3" system? I'm saving for Cobra de-cat but louder version!!

 

If you want a loud cobra exhaust system 3" downpipe 3" centre section non resonated and there sb17 tail pipe much louder than a biltz nur spec

 

Your other option is to go full de-cat and change your back box to something with a small exit. The Blitz is loud due to being a 4.5" exit with plenty of room to cause resonance.

A valid alternative is a RaceBox backbox as it is a smaller exit (3.5" i believe) but will still provide the noise you desire. A friend of mine has a full de-cat with this backbox on his Spec-D (470bhp fully forged) and it sounds good, should keep the neighbours happy as well