I already talk whit a person that know, and exhausts are his live.

But I would like to know/ear/read your opinion.

Whit a up-pipe + downpipe + back-box (de-cated) if i fit my OEM old shape Impreza center section, what are the changes?? What I loose??

When I fit a better turbo an another parts that I think will go for 300 - 315hp this mod in exhaust will "live"? Gas flow?? Gas temp.?? Reliable of the part?? etc.

What do you think.

Thanks.

Mine felt slower when I put it on. Quite obvious. Get a sports cat from someone like Milltek/Miltek (spelling?) who seem to show good results if you need a cat.

Or just keep it in the garage for emmissions tests....

Richard

There are reports that the centre cat on it's own will die after prologed use. They are designed to work with a DP cat.

Save it for those MOT days.

F

Thank you fpr your answers....................,
Ok I will say way I want to fit a cat.
How can I have less NOISE!!!!
I probably will fit a up-pipe. I already have:
Down-pipe + center + back-box de-cated system.

Could you help me!

PLEASE I need that my exhaust make less noise.

Thanks

PS: To Jonh Banks whit the ECUTEK the car makes more or less noise??

The ECUTEK won't make any difference to the noise level. Well, conveivably a little more under full boost as there's a little more air to shift, but that's it. And I don't think it would be measureable.
There's a trade-off for noise/flow - got the 315ish bhp bit to aim for, but with which mods, how 'quiet' is 'quiet' to you, and what part of the noise at the moment is it that you are finding loud - noise on-boost, off-boost, or at cruise?
Loads-a-questions :D
It would help to know what you are finding 'loud' at the moment as well! What's your current system (brand rather than just de-cat!)
Then I'll have a bash at an answer :)

Floyd,

My centre still passed an emmissions test after having previously done 30k km's duty as the sole cat.

Richard

Richard

I stand corrected in your case ;)

You probably don't drive very fast anyway ;) ;) ;)

F

To Nom.

My parts are all Scoobysports (I have a quiet back-box)
The off boost sound it is just a little loud, but when the boost wake up .............. it is very very nice but believe me it is loud.

Thanks

You could fit a centre with resonator to reduce the noise, or more soundproofing to your car if it's the cabin noise you want to reduce.

Stefan

Ozzy makes good points - but the ScoobySport BB is very noisy. It's just about right with the oem catted DP I found (although misses the hard edge that it gains without the car that makes it sound so good!).
Resonator will help. Centre cat will help (there are 'performance' cats that are much less restrictive - I have one & compared to the straight-through it's barely noticeable, apparently the case up to about 360bhp).
On-boost noise is caused largely by the DP AFAIK, but that should be OK if 'mediated' by the backbox. Or so is my understanding after never-ending playing :rolleyes:
Other things to try - change the DP for a quieter one - I believe the BPM is the quietest around while still performing well - or change the BB for a quieter one. The BHP you are after shouldn't restrict the choice too much - I found the TSL to be a good compromise myself; it is quieter than the old Scoobysport BB all-round, but also less droney - more raspy. The quietest by far is the Remus - it is a little restrictive though for the 300bhp area, and it tones the exhaust down to such a point that the car sounds more like a BMW!
So, there you go - more things to muddle you :) Sorry! ;)

[Edited by nom - 10/16/2002 4:58:44 PM]

ScoobyWhite

I you feel you must fit a Cat http://www.milltek.co.uk/subaru

Otherwise get a centre section with reasonator (ie) STi. I found this quieter than OEM centre section with ScoobySport DP and BB

Prodrive boot carpet cuts down on in car noise, lay it on top of the standard one