I have asked this before but did not take it any further... I have been told on here if I remove a "centre exhaust section" I would get an improved "subaru burble" can someone point me in the right direction with prices please? Does this mean I take out one of the CAT's? One other quick question if I decided instead to buy either a CAT back system or back box which system would give me a nice sound for every day driving but on long motor way drives not give me a headache.... thanx all as usual.

 

I have the turbo back Milltek 3 inch exhaust on my GB270 wagon - this removes the cat in the downpipe which helps to improve spool up (I believe) and a resonated centre section with a sports cat so it passes MOT's (although you need to get the cat good and hot to pass emissions).

Sounds really nice around town/general use and sounds great when giving it a bit of throttle. It is noticeably louder/drones a little on the motorway at about 70 - but it is supposed to be one of the quieter aftermarket exhausts - I find it OK for longs runs personally.

Milltek exhausts are pricey though as are all decent stainless aftermarket jobbies but decent second hand exhausts seem to come up for sale quite regularly.

I'm pretty sure you will need a remap if you have a full/turbo back exhaust reaplcement or remove one of the cats but could be wrong?

Time to start modding

 

So the CAT back option keeps the CAt in place so would pass emisions test still. Have thought about a full one but I dont want to because like you say would prob need a remap and I dont want to do this yet..

 

I have the Milltek 2.75" Back box and center section along with a Cobra 2nd decat pipe so still has one cat in the downpipe. Nice sound, not silly loud passes mot no prob.
I would think you already have the second cat removed as part of the power hike to 270bhp.

 

Or try one of these http://www.scoobyparts.com/acatalog/...REAR_PIPE.html

I`ve just ordered one to give me a bit more burble (I hope).

 

So if I ordered a replacement rear pipe and see what it sounds like with the existing prodrive bits then I should be able to hear a difference? and worst case I just by a different back box if I dont like the sound? Also does the GB270 only have one CAT then?

 

No - GB270 has two cats as standard WRX/STI - just had a look at the old exhaust in the garage to confirm - it's just the Prodrvie backbox replaced.

There are PDF manuals you can download from here that show this as well - parts 2 and 12 on the centre and rear exhaust section.

Find someone local to you with a 2.5 hawkeye with aftermarket exhaust or go to a meet and ask to have a listen - you know what you'll get then and a good excuse for a drive!

The Scoobyparts rear section replaces the resonator/chamber I think so you keep both cats still and therefore no remap required?

Think about what future modding plans you have if any and work from there.

 

The back box makes a bit of difference (depending on what you choose) and replacing the center pipe with a deresonated (straight through) pipe will add to the sounds.

 

Milltek MSSUB 114 and MSSUB 115 are what I have.

 

Can you tell me please where these manuals are on her please.. thanx all so far.

 

https://www.scoobynet.com/technical-...d-updated.html

link below to Technical topics which is useful

https://www.scoobynet.com/technical-topics-archive-427/

 

is there one for my gb270 please?

 

No - GB270 is a WRX with a few added bits - the standard 2006 onwards WRX/STI manual covers this car with the exception of the add-ons.