Gary WRX

Hi all

I am planning on a remap with Racedynamix (220bhp-260sih) and trying to source parts is giving me a headache as I am new to all this modding lark. I think the items listed below is all I need but can you guys advise if I need anything else?

Car is an 03 WRX Blobeye

First I am looking at the back box from Cobra Sports
SB02 Subaru Impreza Turbo WRX / STI (2001-2007) - Cat-Back System (Resonated)

• Fits - Impreza WRX/STI
• Engine - 2.0 & 2.5 Turbo
• Year - 2000-2007
• Parts Inc. - Centre & Rear Sections
• Resonated System = with centre box (Recommended option)
• Bore size - 2.5" or 3"
• Power Gains - (Est) up to 15BHP

£280.00



Secondly the front pipe (is this the same as an up pipe?) also from Conra Sports...




SB26 Subaru Impreza Turbo WRX / STI (2001-2007) - Front Pipe & Sports Cat

• Fits - Impreza WRX/STI
• Engine - 2.0 & 2.5 Turbo
• Year - 2001-2007
• Parts Inc. - Front Pipe with 200 cell high flow sports catalyst (Open Neck)
• Bore size - 3"
• Power Gains - (Est) up to 15 BHP

(Note:- Does not include the turbo gasket)
This part, when fitted, will still enable your car to pass a UK MOT emissions test.
This is made with T304 grade stainless steel, mandrel bent and Tig welded which will allows a smooth flow to maximize power gains.
ÂÂ

£225.00



As far as I can tell I can either go for the above Front Pipe and Sports Cat or a full decat as below (am i right its one or the other here??) Would there be a significant performance benefit from the pipe below vs the one above as both state high flow? Full decat appears to be cheaper but then I guess I have to pay to have it put back on for my MOTs afterwards


SB25 Subaru Impreza Turbo WRX / STI (2001-2007) - Front Pipe / First and Second De-Cat Section

• Fits - Impreza WRX/STI
• Engine - 2.0 & 2.5 Turbo
• Year - 2001-2007
• Parts Inc. - Front Pipe De-Cat (Open Neck)
• Bore size - 3"
• Power Gains - (Est) upto 15 BHP

Fitting this part will cause your car to fail the MOT, as it removes the first and second catalysts.
This is made with T304 grade stainless steel, mandrel bent and Tig welded which will allows a smooth flow to maximize power gains.
Â

£135.00



And lastly K&N panel filter (£50 from Scoobyclinic)


So i think that is everything i need in terms of parts so if I add the remap at £350 i am looking at around £900 all in plus fitting of the exhaust is that about right?

Any help/Advice would be great
Cheers
Gary

leecalcars

iTrader: (37)

Sounds like a good start give duncan a ring he will put you in the right direction he did me !

pinkypurkhardt

iTrader: (9)

the "front pipe" is the down pipe mate i think as it is refering to open neck, the decat will have to be replaced for the mot but will give better spool the sports cat is a good option though and you can remove the second cat and the up pipe cat to, also look into a walbro fuel pump mate and a prodrive 3 port boost solinoid fb tuning on here does them for £60 i think mate but as above ask duncan he will put you right mate and enjoy he will make make the car feel so different did an awsome job on mine

dynamix

iTrader: (3)

An easier and perhaps cheaper option Gary would be to call Alyn at AS Performance and order a Miltek 3 inch system from him. They are a great system (and sound superb too) and will fit perfectly - I am sure Alyn will sort you a great price

Either way, whether it be sports cat or full decat downpipe (front pipe according to cobra's description, but not everyone elses) it will make more than the 260bhp

MDS_WRX

iTrader: (1)

You've got it pretty much spot on Gary and have come to pretty much the same conclusions as I have as I'll be doing exactly the same to my 2005 WRX this year.

I'll be going for the:

SB02 Subaru Impreza Turbo WRX / STI (2001-2007) - Cat-Back System (Resonated)
SB26 Subaru Impreza Turbo WRX / STI (2001-2007) - Front Pipe & Sports Cat

as I don't want to have to worry about swapping stuff over at MOT time and I've already put the K&N filter in. You also need to decide whether to go for the 2.5" or 3" sizes; the 2.5 will be quieter and will be a little bit more restrictive.

From what I've been told things like Walbro Fuel Pumps / Induction Kits etc won't be needed for these levels of mods, but that something you might want to consider is an uppipe from Harvey as well as the other bits listed as this will help a lot with the airflow (not sure on the exact price though so you may want to drop him a PM).

With all that you should hopefully be looking more towards 280+ rather than the 260.

JAutos

iTrader: (5)

Hi mate, I have a bug eye 2001 wrx and am pushing around 275bhp (EST by Duncan from race dynamics as he does my mapping also) can certainly recommend him 110%.

My specs are 2.5 inch stainless exhaust from downpipe back. which has the second cat removed. 3 port boost solenoid which i would advise strongly if you are wanting a little more power as it allows you to up your boost to around 1.3 bar safely while without it your limited to 1.1.

To explain the exhaust you have the uppipe which connects the turbo to the manifold/headers. Unless you have an STI this has a small cat in it also which is why replacement uppipes are a good idea. Then the Downpipe(frontpipe as listed with cobra) has a 2 piece part with two cats, If you only want to decat the second cat you need the short pipe, the SB25 is the decat which replaces both parts of the original system cats, as does the sport cat.
You can also buy decat just for second cat also.

HRC fuel pumps are 2 year warranty and quiter than the Walbro ones also. and Cheaper.

Wagon Gaz

iTrader: (18)

Like Duncan says have a look at Milltek, its very good quality, the other thing I would recomend would be a Walbro fuel pump and silicone hoses for your intercooler conections as the standard setup is fairly poor.

Duncan is mapping mine on Sunday

s70rjw

iTrader: (2)

As suggested, the Milltek 3" system fits perfectly and sounds subtle at motorway speeds, but nicely throaty as the revs rise. For the price of a Walbro or similar fuel pump, replacing it is a no brainer. The car running lean can have catastrophic results which will cost far more than the price of a fuel pump.

Gary WRX

Thanks all for your suggestions I will take note of the fuel pump and add to my list

Duncan - cheers for the heads up I will contact Miltek and speak to them

JAutos - thanks for the comprehensive explanation it's really helpful

Gary

Norman Dog

iTrader: (1)

I would definately decat the up pipe while you're doing the mods, I have the same car as you and this is the spec.

STi up-pipe
Prodrive Sports Cat Downpipe
Hayward and Scott decat centre pipe
Pipewerx stainless catback exhaust with deresonated centre section
NGK PFR7B Spark Plugs

Worx tuning (hybrid) dual stage blow off valve
Samco Intercooler Hose Kit
TSL Group N Panel Filter

Remapped by Andy Forrest 287BHP 307 lb ft Torque

Gary WRX

Thanks fella looks like you've got some strong figures out of your upgrades!

harvey

iTrader: (48)

To further help you as those above have been trying to do:
Up to and above 400 bhp it matters not whether you have 2.5, 2.75 or 3" exhaust system but it is nice to go for a 3" system to cater for project creep and it will always sell easier if you want to change it in the future.
Sometimes a 2.75" system is actually referred to as a 3" system. Not a problem.
The WRX has a downpipe and link pipe. This can be replaced with a WRX downpipe.
The downpipe is the pipe that goes from the turbo exhaust/back end to meet up with the centre pipe which may or may not have a resonator box in it followed by the tail pipe and back box.
Not all exhausts are as condusive to power delivery as others so go for a proven system which is generally fairly straight and uncomplicated.
A Walbro GS342 fuel pump 255 lph is the right one for your car. Costs about £75 or £100 fitted. This is usually the starting point followed by the exhaust followed by ported headers and matched uppipe.
Totally decatted and mapped these cars will produce 280-295 bhp typically.

Gary WRX

Thanks Harvey for the additional advice. I'm now sorted and booked in for fitting and the map early Feb I can't wait!!!!!! I'll update on how I get on when it's done