toner13

Hello
New to owning an Impreza I have a 2003 WRX Sport Wagon.

There is a few questions I have.
First is what is the standard oil pressure reading In (BAR) I should be getting from a gauge and second is the standard turbo Pressure reading but in (PSI) on a gauge.

I am thinking about exhaust systems to at the moment it has a Centre Rear Exhaust with a pro drive back box nice sound and don’t want to make it much louder what options would people advise for cat upgrade? Don’t want to D-cat for MOT reasons.

Looked at: Sport Cat Downpipe with De-cat front pipe

Sport Cat but with De-cat Up pipe



Or do I need both Sport Cat Up pipe and Cat part to pass MOT. Having two has confused me a bit and any recommended makes would be helpful. What sort of BHP could it get without remapping?



Thanks

jura11

iTrader: (7)

Hi there

Oil pressure should be around 6-7bar when engine is cold and around 2-3bar on tickover/idle when is hot,this have lots of variables like what oil is used etc.

About the exhaust I would go down the route of the sport cat(100CELL sport cat) and centre pipe with those you should be able pass MOT without the problems

Decat Up pipe I would go down the route of the STI or Classic Up pipe,both are decatted and both fit yours without the problems,if its budget then Harvey Up pipe which selling Alyn@AS Performance will be best choice

Yes remap is highly recommended and you will need at least due if you will fit decatted up pipe which doesn't using or doesn't have EGT,you will have few troubles in cold weather with EGT,due this I would get car mapped or if not then drive off the boost until car is mapped

Without the mapping hard to say,you will not gain lots,car will be running like very rich and you will suffer with worse MPG and CEL(Check engine light) etc

With mapping I would expect around 270-280bhp on yours

Hope this helps

Jura

toner13

Hello

Thanks yeah I am getting those read outs from my gauges so that’s good.

I worked out I want to change the down pipe next looked at the STI and will look at Harvey pipe to. So I would need to get it mapped if I changed this then or ill get problems.

Quite happy with it at the moment but 300 320 would be nice.

Thanks for the info

Dan wrx

iTrader: (2)

To get 300-320 you will need bigger turbo, injectors, decent panel filter, upgraded fuel pump, as td04 is good for about 280 max really,

toner13

So probably best to get all done at the same time. What Turbo Would be best and injectors. Sorry a lot to learn about .

Any Idea what the standard Max Turbo Pressure reading should be (PSI)

Thanks

Dan wrx

iTrader: (2)

Should be about .9 bar I think, don't hold me to that though I'm sure someone else would be able to confirm that, and I've gone for a td05 16g, sti up pipe pink injectors (still to get) decent panel filter de cat exhaust and I should see about 320-330 bhp (roughly) but there's many discussions on here about what turbos best, some say the vf range is better some say the td range is better just depends how you want it to boost I suppose

Dan wrx

iTrader: (2)

+ fuel pump

toner13

Thanks yeah ill have to have good read about, there seems to be a lot of options anything over 300 would be nice. I have a K&N panel filter I think they are quite good.

jura11

iTrader: (7)

Hi there

Downpipe with Harvey Up pipe and you have nice combo with those mods you should be able to run around 270-280bhp

For 300-320bhp you will need turbo and bigger injectors(STi pink injectors) and I would strongly add new fuel pump 255LPH in yours case

Standard turbo or OE boost is around 0.5bar(JDM WRX have standard or OE Boost 0.9-1.0bar due this JDM WRX making as standard around 250bhp),when car will be mapped on current turbo you should be able to see on boost gauge around 1.2-1.4 bar,but again but,sometimes more boost doesn't mean more power

If you are looking go above 300bhp,good start is get TD05-16G or VF35,both can be easily modified to billet and for billet upgrade you are looking at around £190 for VF35

With Billet you can gain like on top end and on the spool up

Hope this helps there and good luck

Jura

toner13

Hello

Thanks will I still need to Map after fitting a Harvey Up pipe to stop getting problems running? and what price are they? I’m getting about 15-16 psi on my gauge at the moment.

jura11

iTrader: (7)

Hi there

Personally I would get all parts fitted,which you want to have fitted and then get car mapped,until map try do not push car and try drive off the boost

Yes you will need get car mapped and boost what you are running seems is correct,but maybe I'm wrong

Jura