Newbie here guys ive just introduced myself in the greetings forum,however im after a little info. im from uk but now live in nz and with the scarce parts here its hard to get stuff so ive imported a few things from the uk.Basically ive just brought a immaculate st205 ra which is pretty hard in nz as everything is knackered.Anyway ive ordered a decat pipe as we dont need them here for emmisions.The main thing i want to know is the boost tap/bleed valve.???ive seen the plumbing it in with blanking the other side of the actuator off but obviously you raise the boost until just before the fuel cut?around 1.2bar?What i want to know is how much more bhp does the car make with just raising it as ive read up on the net about these motors being hugely over fuelled from factory?
hope you guys can help sorry if youve heard it all before but theres not much info on them here.

to raise the boost you will want to use a electronic bost controller in my eyes, manual bleed valves... not really my cup of tea.

as for fitting it, once you have fitted, make sure you block off the tvsv or it wont boost properly, the fuel cut comes in at around 1.25bar and yes the fueling is rich from the factory however the ecu only has fuel maps upto 1.2 bar, so anything over and the ecu really doesnt know what its doing.

get yourself a boost gauge, an electronic boost controller with a boost gauge built in too like a blitz spec-s or spec-r and then raise the boost.

To get c300+bhp SAFELY...

De-cat the exhaust
Uprate the rest of the exhaust to a 2.5, 2.75 or 3" diamater system (Mongoose, Blueflame, Blitz Nur-Spec, ...).

Get an uprated panel filter (e.g. K&N or similar)
or go for something like an HKS mushroom filter (or similar) setup (you may need a cold air feed to the filter).

Higher grade spark plugs (grade 7).

Boost Controller (Blitz, HKS or Greddy) - I would advise having this setup on a rolling road or a safe place on the road - You wont to make sure that your air/fuel ratios are correct so use/borrow a wideband AFR meter.
I believe fuel cut on the standard ecu is just above 1.2bar.

Many people just want more power but forget about the cooling side of things.
You up the power you generate more heat so you need to take into consideration the cooling side of things.

So...
Intake temps can be an issue so get some heat resistant material and lag the charger cooler.

Consider an uprated radiator (e.g. a Koyo) and thermostat (TRD).

You may want to consider an uprated engine oil cooler.

GAUGES - get some gauges - you want to know what's going on.
Oil pressure, oil temp and water temp as a minimum.
(A Boost gauge is only really necessary if the boost controller doesn't have a reading).

HTH

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