What next on my 2003 WRX power wise?
 

After uprating the suspension and brakes I'm looking to improve the power/torque on my 2003 WRX just to improve the driveabilty. Its in for a 50,000 mile service later this month (incl cambelt change).

I have already purchased some blue injectors (now cleaned and flow tested) and a VF43 turbo off a 2007 Sti. A green panel filter will be fitted at the service and there is already a straight through centre pipe (ie no resonator) and a Racebox exhaust fitted.

Questions I have - will I need an uprated fuel pump? Is a decat uppie pipe a good choice (I don't want to be messing about changing pipes come MOT time). Is a decat uppie a better choice than a decat down pipe being in mind the MOT emmisions requirement.
Any preference on spark plugs ? Fuel is Shell V-Power.

The service is being conducted at Thwaites Developments in Warwick and I was going to ask these guys to carry out the work and offer their advice on mods too as they have mapping facilities there.
Any preference on spark plugs ? Fuel is Shell V-Power.
Any help/advice welcomed....

Hi chap, sounds like your going down the same route and mine. I'd say the fuel pump upgrade is not existential as the newage pumps are more robust and can handle up to about 290bhp. As far as the pipe work goes I'd get the decat down pipe, up pipe, striaght through centre section and race box, then keep the last cat in place for mr mot. You could also get a 100 cell sports cat down pipe if you want the most bhp out of your system but still road legal. Shell V-power or Tesco 99 Ron get my thumbs up to.

For how much a fuel pump cost's i would certainly replace

im sure for you to get the most out of those mods, a remap would be in order, contact the person you choose to map the car to advise on other mods, im sure a fuel pump and decent plugs, along with those mods would see a healthy gain.

good luck with it all

See if you can get an STi pump as loads of people get rid for a Walbro. But I would definetly get a better pump as it may lean out if you increase BHP/Torque with a remap, all mappers recommend them

The Newage have an up and down pipe cat, depending on MY. The third lump in the exhaust under the drivers arris is a resonator and does feck all for emissions just noise. A down pipe cat replcement would allow the fitting of a sport cat later.

A better panel filter is also a good idea, big choice here. The standard airbox can handle + of 400BHP (CS 400/Litchfield Type 20). Even think about an STi intercooler as it fits straight in and the holes are already there.

With these mods and a good mapper you should see 280ish bhp and similar torque.

:thumb: