fergie_uk

Hello ladies & gentlefolk of scoobynet, im after some advice from you folks. Ive come into a wee bit of spare case and would like to enhance the performance of my Subaru.

Firstly the make

Subaru Impreza 04 WRX STI Type uk
Mods so far are minor

STI performance Panel Filter
Afterburner Backbox

I now want to go the full Decat route to bring in a bit more torque and to allow it to spool up a wee bit sooner oh and to free up some more horses.

As i have no clue as to which parts to get im now in the hands of you folks, i believe ive identified the parts required but would appreciate some feedback so i dont make the wrong purchases.

I believe i need the following

Decat Openneck Downpipe (With CEL Fix?)
Decat Mid section (With CEL Fix?)

ECU Remap (Later im hoping?)

Im going to purchase from
http://www.cnewt.co.uk/products.asp?cat=6&sub=6

And would appreciate some feedback as to the sections i need.

Im ok with warrenty as its a company car and the boss has given me the go ahead.

I guess my first question is will it be ok to do this without a remap if so have anyone else done this on a newage without a remap and what gains were made?

Any help would be greatly appreciated.

Regards
Fergie

fergie_uk

bttt

fergie_uk

for getting slaughterd in another fourm , any one done this ?

Brun

Now, now - i didn't slaughter you
I'm not sure what the score is with the blobs, but is there not a boost spike problem with decatted Bugs? Could be the same! I could be talking **** actually as i know there was this issue with the P1.
Tek 3 would be ace with a decat on your car as you will easily crack the 300 mark and would probably be closer to 320+
Again - i'm not 100% about the Blobs, but the downpipe CEL fix could be an issue. I don't think this applies to the mid section.
Above all - with the mods you're planning - i would be inclined to fit a knocklink and AFR, just so you know whats going on

Are you sure the boss knows what the warranty implications are with the decat?


Ps - i can be helpfull when i try

fergie_uk

Much better Brun, thanx for the info, ive calmed down now. So is there anybody out there thats done this to there Blob Eye?

Regards
Fergie

XS-Home

Hayward & Scott will assist & I think maybe doing a group buy call Ian on 01268 727256 on Monday - he'll sort you out a treat

fergie_uk

1 last bump

hades

CEL fix is only relevant if you decat the downpipe. Also, if you get an ECUTEK remap, they can sort out the CEL issue in the map, so you wouldn't need a CEL fix.

As Brun mentioned, a lot of people with the bugeye STi found that fitting a decat caused big boost spikes, which could potentially result in blown engines. Two ways around this - the quick fix is to change the restrictor in the relevant hose to drop the boost. By far the better way is to get the car remapped (ECUTEK).

In your position, if you want to go in two stages, I'd do:
step 1 - centre de-cat only (no CEL fix required)
step 2 - downpipe decat and remap at the same time (no CEL fix required as remap will handle this)
If you fit the downpipe and then drive it to the mappers, then drive it there gently and keep it off-boost, it should be OK.

Ecutek'd and decated STi's will typically make anywhere up to 340bhp at Power Engineering's (fairly optimisitic) rollers. IMHO, the bigger benefit is that the turbo will wake up at a lot lower revs - no more waiting until nearly 4000rpm for the performance to suddenly arrive.

fergie_uk

Thanx Hades, so centre section it is first then, are you sure no CEL fix is required for centre decat only? , and what centre section do you suggest?, sorry but there's a minefield of choices and im not sure which.

Regards
Fergie

hades

Yes, I'm sure no CEL fix, no boost spike problems for centre section only.

To be honest, there's not a lot between different makes of centre sections - they really aren't much more than a slightly bent bit of pipe. If you're replacing the "rear centre section (between the cat and the backbox), then resonated ones are quieter than non-resonated, which is about the only decision you might want to make. As you're replacing it in sections, you'll need a 2.5" rather than a 3".

If you liked the service and product with your afterburner, you might as well go back to scoobyworld and get the centre section they recommend - chances are it'll be one made by Hayward & Scott who are generally well regarded.

fergie_uk

Hades your a Star

boothy

Fergie i have just replaced the b/bpx on my 03 wrx and toomorow i am fitting a decat centre section i have also fitted kn filter am looking to have remap done next will keep you infprmed if you wish

fergie_uk

boothy, im still confused as to what to purchase, im currently looking at Scooby world and am unsure as to what to purchase, do i need the centre section and the Afterburner Cat Pipe or will the centre section do the job on its own??? please help cash burning a hole in my pocket.

Fergie

hades

Your car has four parts to the exhaust:
The downpipe (don't change without a remap).
The "front centre" section, or "cat pipe". Call this part "a"
The "centre" section with a resonator in it. Call this part "b".
and finally the backbox - already changed.

You definitely want to change part "a", and will get a small benefit for changing part "b" as well. Let's assume you go to Scoobyworld, (and assume I'm reading their website right!):

Buy their "afterburner cat pipe" to replace part "a"
To replace part "b" you have two options - "afterburner centre section" or "ninja centre section with integrated silencer". The afterburner centre section will make your car noticably noisier than it is at the moment. The ninja will be a little quieter and noticeably less "boomy" due to the integrated silencer. Power wise, you'll probably never notice a difference between these two products.

If you're confused - talk to the dealer, if you go to meets, talk to people there, get them to show you.

~~ Cal ~~

Hades - ypou are the main man

Just the sort of helpful post that restores my faith in SN

Cheers
Cal

fergie_uk

Hades your the man, now where that credit card!!!

Thanx again