Had the car a couple of months now and I don't know whether we are just used to the sound now but now feel the volume needs turning up. Sounds great close up with a nice deep driver friendly burble, but after 50m or so it loses it's character. The cabin noise at the moment is very bareable, not intrusive at all. Also I've followed my Mrs in it and the noise doesn't match it's looks, and sounds a bit lost amongst other traffic. We're after something louder but not too loud, don't want that Corsa, VTS strangled cat sound!!

I've read through the forum but I'm non the wiser really, some say change the back box, some say change for de-resonated centre section

Anyone been through the same experience?

Car is: 06 Hawk WRX PPP, re-mapped to 266bhp
So exhaust is (as far as I know) Prodrive Stainless Turbo back?

Questions are:

Has the Prodrive Exhaust de-res centre section?
Is it just this that needs replacing?
Or just a rear back box?
Anyone know the bore of the existing Prodrive Exhaust? (guessing 3")
Will it need re-mapping after the work is done?
MOT friendly?

Apologies for all,of the questions, just know Ill get the right answers here.

In short what do I need to do to get the desired sound? Happy to pay to get the right sound

Thanks, as always, for taking the time to read or reply. Any help is greatly appreciated

Gaz

 

Hi Gaz,

As you know I run WRX 05 PPP. It came with 2.5 inch Prodrive system but found it too quiet.

I did try a Ninja 1 back box but it did not make much difference too be honest.

Went for straight through centre pipe & back box & it has had the desired effect, nice deep burble, not annoying on motorway runs & when foot goes vertical people know your coming!

Did not have to have a re-map as I only went cat-back.

Hope you find what you're after mate. Dunno if it's a bit of pot luck with the sound or whether some ppl are too fussy but some guys on here have changed their systems several times in trying find a particular sound.

Hope this helps in some way.

 

If it's the WRX PPP I believe the exhaust will only be cat-back not turbo back, so any gains will be limited.
You're lucky as from Hawkeye on the cars don't have the cat in the up pipe so it's one less thing to change and the engine is less restricted (earlier WRX models had an additional cat in the up pipe).

To get more sound (and power) you can either replace the catted down pipe and centre section with an STI PPP sports cat and decat centre section, which will get you probably about another 15-20bhp if you have it mapped, OR you can go full decat for a small increase but then you'll need to change it come MOT time (or find a suitable station )
TBH if you're running the standard turbo I'd suggest sports cat - you can often pick up the pair for something in the region of £120-150.

A mate is on the full Prodrive system with a decat down pipe and his is louder than my Zero Sports 3" system. I actually think a full prodrive system sounds pretty sweet.
If you want mad loud then buy a Blitz Nur Spec but be warned it's not for the faint hearted!

 

Cheers for the reply both, really helpful, think you may be right To, bit of luck involved in achieving the right sound. I found this on t'internet:

http://www.subaru4you.co.uk/exhaust/centrenewage.shtml

Is this what I need to give it a louder sound? And leave the Prodrive back box?

It looks easy enough to swap

Gaz

 

Two things mate; first I wouldn't ever pay that much for a decat centre; they come up here all the time in the for sale forum for as little as £25; usually max £35.
We're talking Prodrive stainless jobbies here.

Second I'd also do the down pipe at the same time.
The gain you'll get from going to just a decat centre will be less noticeable than if you do both.
That's why the STI PPP cars had both those pipes
The car will still pass MOT no problem like that.

Any questions drop me a PM but I'd save your money buying it new and have a hunt on the for sale forums. If you can't find one try Scott @ Scooby Spares.

Hawkeye WRX's with the 2.5 engine and this exhaust setup with a good panel
filter often make just in excess of 280bhp and 320+ torque with an engine map.
HTH

 

Thanks for the replies, we got a Japspeed centre pipe in the end and had it fitted, it's given 50% more burble with a deeper, noisier burble, but not too loud. Suits us perfectly and really happy with it. Anyone thinking of going down this root won't be disappointed. Its matched up to a Prodrive back box.

Cheers

G&G

 

I was going to suggest the centre pipe replacement route but you beat me to it.
My 06 Hawkeye Spec-D just had the centre pipe literally sever in two between the resinator and the first cat.... bad for the exhaust (and my wallet!) but holey crap did it bring out the burble and sound good!
I was surprised as the research I've done on here suggests its the equal headers on the 2.5 that causes the loss of burble. It may contribute to it for sure but this un-predicted/unwanted test of mine has proved to me that the burble can come back a bit with the centre pipe resinator removed (and a decent back box would help no doubt).
You should try and get a video/audio onto youtube with it... I'd be interested to hear the difference as I'm not looking for crazy loud. I'm going to post a vid of mine with the snapped exhaust just for comparison and giggles!

 

That's correct, it's the unequal length headers that cause the traditional Subaru burble.
JDM cars have equal length headers as standard.

 

http://www.youtube.com/watch?v=hyvPI...ature=youtu.be

This is the noise that is being created by my severed centre pipe... sounds burbly to me (oh and the initial noise is the neighbour driving off not the scoob!). Probably not wise to go chopping your exhausts in two though!

Standard pipe replacement pipe goes back on over the weekend.