hi i got a 2005 wrx with an sti ver7 shortblock fitted as the wrx block gave way to bigend failure.other than that its all standard.so now i am used to the wrx power,i am thinking i would like another 50 ish bhp and more torque? big thing is though ,what's the cheapest cheapest affordable way to achieve this? anyway to do it with a £500 budget?

 

2005 WRX is 225bhp I think. You'll be able to get 280 out of your TD04 turbo (a 55 increase - as per your desire ;-))

You'll need:-

- Walbro 255 pump = £70 new
- Fresh panel filter (OEM paper/Apexi/Green/K&N) = £30-40 new
- Fresh plugs (NGK PFR7B's preferably, gapped to 0.6-0.7mm) = £20-30
- Single decat downpipe to replace the OEM dual-cat, 2-part job = £60-100 2nd hand
- ECUTek remap of your OEM ECU = RRP £632.50 (all in)... includes licence (one off fee) plus 1st map

You're looking at between c.£800-900 (not inc. any garage fitting costs)... but your engine will be SAFE!!!

 

when you say dual cat this means there are 2 cats? so i guess the second down stream cat will be replaced with the decat? back box to be changed also? will this decat pass mot emissions testing?sorry for so many questions.what if second hand sti parts were fitted say ecu,turbo injectors,fuel pump and exhaust would this be cheaper?

 

- Yeah, New Age WRX OEM 'downpipe' is in 2 sections; a cat in each.

- Full system prob isn't needed to get the full extra power/torque the TD04 offers, but obviously nice to have a decent aftermarket centre and rear box of course (and WILL be freer flowing).

- You still have a 3rd! cat in your up-pipe, but not sure if it'd be sufficient on its own to get through MOT though...

- I see what you're saying about the STi gear and I think, in theory, it should work if you just swap out the WRX items... BUT... the cost of the STi turbo (VF43?) itself will eat into the potential 'saving' (over what I suggested in my 1st post) as well as the labour to fit it (unless you're handy with the spanners). Plus the TD04 is more responsive than the VF43 - so if you'd be happy with 280 and no more, then the TD04 will be a better choice for that power level i.e. really good early spool-up (esp. in conjunction with its bespoke map!)