Impreza tuning

[Jamiest]

Hi guys 

I'll start of by saying sorry lol

I no you've probably been asked or seen this a thousand times but I've been a lover of Scoobys for 15 years but never actually brought one but now in the process. I'd love a p1 but I'm not minted.. So the questions.... I'm looking at either a uk 2000 or I've seen a nice 2.0t 2005 completely standard ( not interested in someone molested scooby) full subaru service history etc etc and looking where to start from the very beginning with tuning her.... intake . Exhaust. turbo . Etc etc etc i no a bit about mechanics and really like some help where to Starr. 

 

Thanks

[Sandals]

Welcome to the club!!

Are you looking at getting an STI or a WRX? 

I would leave the intake alone, just get an uprated panel filter

Exhaust - You can do cat-back and leave all the cats in place so you don't have to remap or go all out and go down the full decat/sports cat route

Uprate the fuel pump if you go for a remap

If you go for a WRX, you can then look to upgrade turbo and injectors as they run out of puff around 270ish

That's generally a good starting point!

 

[Jamiest]

First of all thanks for the reply .

Been looking at the wrx . Could you explain "cat back " sorry 😶 

 

[Sandals]

2 minutes ago, Jamiest said:

First of all thanks for the reply .

Been looking at the wrx . Could you explain "cat back " sorry 😶 

 

No problem!

The exhaust system is split into different sections:

Engine > Exhaust manifold/headers > Up-pipe (has a catalytic converter usually) > turbo > Downpipe (Main catalytic converter) > mid-pipe/cat pipe (contains catalytic converter) > Centre section (has Resonator) > Back box

STI does not have a catalytic converter in the up-pipe (along with anything after 2006)

So a cat back system is when you only change the back box and the centre section, you can go non-resonated for the centre section for extra loudness but may drone depending on the back box you go for. This is a good idea if you don't want to go down the remap route

[Jamiest]

Ok now I understand.  Thanks. 

Is it best to replace the whole exhaust now or at a later date as I will be remapping her but want to make sure everything is right don't want to do things in the wrong order and she blows up or something. Also any recommendations for the exhaust system as I can't get enough of that burble they make 😍 

[Sandals]

If you remove any of the cats, you will need to remap as it could overboost without the restriction of the cats. You can do cat back without a map and it will give you plenty of burble, also fitting an uprated panel filter does not need a remap.

In terms of exhaust recommendation, it all depends on how loud you want to go and how much you're willing to spend...

I have a 2004 WRX, I have done the following:

Cosworth panel filter

STI intercooler

Decat up-pipe and mid pipe, sports cat downpipe and full cat back (still passes emissions)

Uprated fuel pump (Walbro 255lph)

GFB Respons dump valve

Remapped to 210hp and 221lb/ft at the wheels 

[Jamiest]

🖒 rough ballpark figure on what you've done? As and when that gets done what would come next. Ideally wanting around 3-400 . Really appreciate your time and putting up with the bombardment of questions . Thank you 

[Sandals]

Just now, Jamiest said:

🖒 rough ballpark figure on what you've done? As and when that gets done what would come next. Ideally wanting around 3-400 . Really appreciate your time and putting up with the bombardment of questions . Thank you 

I've pretty much taken the standard WRX turbo (TD04) and injectors to their limit... would need to get bigger injectors and a bigger turbo to get into the 300+ club...

The WRX 5 speed is it's weak link, only capable of around 350hp before it breaks. If you want closer to 400 you will be better getting an STI as a base as doing a 6 speed conversion on a WRX is very expensive.

The hawkeye WRX has a stronger 5 speed box, but it comes with the 2.5 which has a higher failure rate compared with the 2 litre (head gasket or ringland failure)

[Jamiest]

O rite ok didn't realise or think about the gearbox to be honest. near or just under 300 would be fine then aslong as engine and box could handle it without breaking Seen alot of people saying pink Sti injectors? Would they be suitable .. and once again probably a stupid question is there anything else needed for the upgraded turbo or will all be ok.  And would I have to remap etc to keep it around 300 ( if it could be acheived) as you said about the box going wouldn't want to upgrade injectors and turbo and it create to much bhp addition and break the box. 

[Sandals]

2 minutes ago, Jamiest said:

O rite ok didn't realise or think about the gearbox to be honest. near or just under 300 would be fine then aslong as engine and box could handle it without breaking Seen alot of people saying pink Sti injectors? Would they be suitable .. and once again probably a stupid question is there anything else needed for the upgraded turbo or will all be ok.  And would I have to remap etc to keep it around 300 ( if it could be acheived) as you said about the box going wouldn't want to upgrade injectors and turbo and it create to much bhp addition and break the box. 

If you change injectors and/or turbo would def need a remap. STI pink injectors would be enough for around 300 mark, not sure what their limit is.

If you want to do it in stages to spread out cost you can do the following:

Cat back exhaust, fuel pump and panel filter - These mods don't require a remap

Then:

Do rest of exhaust, turbo, injectors and possibly bigger top mount intercooler or front mount - Then remap. 

That should see you to 300+ depending on what turbo you go for

[Jamiest]

Brilliant thanks for your help . Now shopping 🖒

[Sandals]

7 minutes ago, Jamiest said:

Brilliant thanks for your help . Now shopping 🖒

No problem!

Cosworth is a highly rated panel filter, I would personally avoid oiled ones as they can potentially knacker the maf... not always but it can happen.

 

[Jamiest]

Yeah already in the online basket lol... £30

[Sandals]

4 minutes ago, Jamiest said:

Yeah already in the online basket lol... £30

Shouldn't you get the car first? :D

 

[Jamiest]

😆 can't help it I've waited so long for this...I feel like a kid at Christmas 😁

[Sandals]

1 minute ago, Jamiest said:

😆 can't help it I've waited so long for this...I feel like a kid at Christmas 😁

Be careful because classic imprezas (up to 2000) and newage (2001-2006) have different sizes for exhaust parts etc

[Jamiest]

Yh gonna go with an 05 i think so have been searching for 05 parts the majority come up 01-06 so guess those years it all stayed the same 

[Sandals]

1 minute ago, Jamiest said:

Yh gonna go with an 05 i think so have been searching for 05 parts the majority come up 01-06 so guess those years it all stayed the same 

It certainly did!

[Jamiest]

Last question ( for now) Bov that flutters is that down to boost pressure and spring colour or is it a different thing all together 

[Sandals]

turbo flutter is not down to bov... flutter is when there is no bov and the air goes back through the turbo, it's the turbo itself that makes the fluttering sound. Some turbos this is not an issue but it does put extra stress on it. You can buy blanking plates for the standard intercooler if you want the flutter.

[Jamiest]

Brilliant thanks for all your help and putting up with the questions. Speak soon 

[Sandals]

No problem buddy, that's why we're here!

[stuartie]

Welcome along, hope you get the right motor soon especially as you're already buying parts 😅, if you decide to go for the earlier classic uk2000 i think they may run the td05 turbo which is the same turbo which is on mine but i have an import so not sure if the jap ones run the same set-up or not someone will be along to correct me if i'm wrong, they seem to be able to handle the flutter better than the newer turbo's so i've read anyways as i love the sound of the flutter and have been undecided so far as whether to do it on mine or not, however as sandy has said it does put alot of stress on the turbine as it can stall it, happy shopping and we look forward to pics 🖒🖒

[Tidgy]

Welcome.

 

First thing to consider is budget. How much you looking to spend in the car and to get it to the power level you want?

[GeoffLeggy]

Welcome! 

You've come to the right place 😉.  I hope you find what you want and don't rush is all I can say.   

As above what money are you looking to spend to buy it?